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authornaruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2015-12-16 05:31:54 +0000
committernaruse <naruse@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2015-12-16 05:31:54 +0000
commitc4fdfabcc8ea3f6186d1560f7756211fce125be3 (patch)
tree52953802cfeae93908e52c59596365a3e946118b /ext/tk/lib
parent183c1a0fa1c9599f613ea8f4c54ed5229354714f (diff)
handle ext/ as r53141
g -L frozen_string_literal ext/**/*.rb|xargs ruby -Ka -e'ARGV.each{|fn|puts fn;open(fn,"r+"){|f|s=f.read.sub(/\A(#!.*\n)?(#.*coding.*\n)?/,"\\&# frozen_string_literal: false\n");f.rewind;f.write s}}' git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53143 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'ext/tk/lib')
-rw-r--r--ext/tk/lib/multi-tk.rb1
-rw-r--r--ext/tk/lib/remote-tk.rb1
-rw-r--r--ext/tk/lib/tcltk.rb1
-rw-r--r--ext/tk/lib/tk.rb1
-rw-r--r--ext/tk/lib/tk/after.rb1
-rw-r--r--ext/tk/lib/tk/autoload.rb1
-rw-r--r--ext/tk/lib/tk/bgerror.rb1
-rw-r--r--ext/tk/lib/tk/bindtag.rb1
-rw-r--r--ext/tk/lib/tk/busy.rb1
-rw-r--r--ext/tk/lib/tk/button.rb1
-rw-r--r--ext/tk/lib/tk/canvas.rb1
-rw-r--r--ext/tk/lib/tk/canvastag.rb1
-rw-r--r--ext/tk/lib/tk/checkbutton.rb1
-rw-r--r--ext/tk/lib/tk/clipboard.rb1
-rw-r--r--ext/tk/lib/tk/clock.rb1
-rw-r--r--ext/tk/lib/tk/composite.rb1
-rw-r--r--ext/tk/lib/tk/console.rb1
-rw-r--r--ext/tk/lib/tk/dialog.rb1
-rw-r--r--ext/tk/lib/tk/encodedstr.rb1
-rw-r--r--ext/tk/lib/tk/entry.rb1
-rw-r--r--ext/tk/lib/tk/event.rb1
-rw-r--r--ext/tk/lib/tk/font.rb1
-rw-r--r--ext/tk/lib/tk/fontchooser.rb1
-rw-r--r--ext/tk/lib/tk/frame.rb1
-rw-r--r--ext/tk/lib/tk/grid.rb1
-rw-r--r--ext/tk/lib/tk/image.rb1
-rw-r--r--ext/tk/lib/tk/itemconfig.rb1
-rw-r--r--ext/tk/lib/tk/itemfont.rb1
-rw-r--r--ext/tk/lib/tk/kinput.rb1
-rw-r--r--ext/tk/lib/tk/label.rb1
-rw-r--r--ext/tk/lib/tk/labelframe.rb1
-rw-r--r--ext/tk/lib/tk/listbox.rb1
-rw-r--r--ext/tk/lib/tk/macpkg.rb1
-rw-r--r--ext/tk/lib/tk/menu.rb1
-rw-r--r--ext/tk/lib/tk/menubar.rb1
-rw-r--r--ext/tk/lib/tk/menuspec.rb1
-rw-r--r--ext/tk/lib/tk/message.rb1
-rw-r--r--ext/tk/lib/tk/mngfocus.rb1
-rw-r--r--ext/tk/lib/tk/msgcat.rb1
-rw-r--r--ext/tk/lib/tk/namespace.rb1
-rw-r--r--ext/tk/lib/tk/optiondb.rb1
-rw-r--r--ext/tk/lib/tk/optionobj.rb1
-rw-r--r--ext/tk/lib/tk/pack.rb1
-rw-r--r--ext/tk/lib/tk/package.rb1
-rw-r--r--ext/tk/lib/tk/palette.rb1
-rw-r--r--ext/tk/lib/tk/panedwindow.rb1
-rw-r--r--ext/tk/lib/tk/place.rb1
-rw-r--r--ext/tk/lib/tk/radiobutton.rb1
-rw-r--r--ext/tk/lib/tk/root.rb1
-rw-r--r--ext/tk/lib/tk/scale.rb1
-rw-r--r--ext/tk/lib/tk/scrollable.rb1
-rw-r--r--ext/tk/lib/tk/scrollbar.rb1
-rw-r--r--ext/tk/lib/tk/scrollbox.rb1
-rw-r--r--ext/tk/lib/tk/selection.rb1
-rw-r--r--ext/tk/lib/tk/spinbox.rb1
-rw-r--r--ext/tk/lib/tk/tagfont.rb1
-rw-r--r--ext/tk/lib/tk/text.rb1
-rw-r--r--ext/tk/lib/tk/textimage.rb1
-rw-r--r--ext/tk/lib/tk/textmark.rb1
-rw-r--r--ext/tk/lib/tk/texttag.rb1
-rw-r--r--ext/tk/lib/tk/textwindow.rb1
-rw-r--r--ext/tk/lib/tk/timer.rb1
-rw-r--r--ext/tk/lib/tk/tk_mac.rb1
-rw-r--r--ext/tk/lib/tk/toplevel.rb1
-rw-r--r--ext/tk/lib/tk/ttk_selector.rb1
-rw-r--r--ext/tk/lib/tk/txtwin_abst.rb1
-rw-r--r--ext/tk/lib/tk/validation.rb1
-rw-r--r--ext/tk/lib/tk/variable.rb1
-rw-r--r--ext/tk/lib/tk/virtevent.rb1
-rw-r--r--ext/tk/lib/tk/winfo.rb1
-rw-r--r--ext/tk/lib/tk/winpkg.rb1
-rw-r--r--ext/tk/lib/tk/wm.rb1
-rw-r--r--ext/tk/lib/tk/xim.rb1
-rw-r--r--ext/tk/lib/tkafter.rb1
-rw-r--r--ext/tk/lib/tkbgerror.rb1
-rw-r--r--ext/tk/lib/tkcanvas.rb1
-rw-r--r--ext/tk/lib/tkclass.rb1
-rw-r--r--ext/tk/lib/tkconsole.rb1
-rw-r--r--ext/tk/lib/tkdialog.rb1
-rw-r--r--ext/tk/lib/tkentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/ICONS.rb1
-rw-r--r--ext/tk/lib/tkextlib/ICONS/icons.rb1
-rw-r--r--ext/tk/lib/tkextlib/ICONS/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/barchart.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/bitmap.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/busy.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/component.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/container.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/cutbuffer.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/dragdrop.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/eps.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/graph.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/htext.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/spline.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/stripchart.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/table.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tabnotebook.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tabset.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/ted.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/button.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/checkbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/frame.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/label.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/radiobutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/scrollbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tile/toplevel.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/tree.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/treeview.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/unix_dnd.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/vector.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/watch.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/win_printer.rb1
-rw-r--r--ext/tk/lib/tkextlib/blt/winop.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/arrowbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/bitmap.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/button.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/buttonbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/combobox.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/dialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/dragsite.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/dropsite.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/dynamichelp.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/entry.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/label.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/labelentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/labelframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/listbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/mainframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/messagedlg.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/notebook.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/pagesmanager.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/panedwindow.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/panelframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/passwddlg.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/progressbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/progressdlg.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/scrollableframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/scrollview.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/selectcolor.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/selectfont.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/separator.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/spinbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/statusbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/titleframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/tree.rb1
-rw-r--r--ext/tk/lib/tkextlib/bwidget/widget.rb1
-rw-r--r--ext/tk/lib/tkextlib/itcl.rb1
-rw-r--r--ext/tk/lib/tkextlib/itcl/incr_tcl.rb1
-rw-r--r--ext/tk/lib/tkextlib/itcl/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/itk.rb1
-rw-r--r--ext/tk/lib/tkextlib/itk/incr_tk.rb1
-rw-r--r--ext/tk/lib/tkextlib/itk/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/buttonbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/calendar.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/checkbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/combobox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/dateentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/datefield.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/dialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/dialogshell.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/entryfield.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/extbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/feedback.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/finddialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/hierarchy.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/labeledframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/mainwindow.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/menubar.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/messagebox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/messagedialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/notebook.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/optionmenu.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/panedwindow.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/promptdialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/pushbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/radiobox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scopedobject.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/selectionbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/shell.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/spindate.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/spinint.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/spinner.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/spintime.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/tabset.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/timeentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/timefield.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/toolbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/iwidgets/watch.rb1
-rwxr-xr-xext/tk/lib/tkextlib/pkg_checker.rb1
-rw-r--r--ext/tk/lib/tkextlib/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/autoscroll.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/calendar.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/chatwidget.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/crosshair.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/ctext.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/cursor.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/dateentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/datefield.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/diagrams.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/dialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/getstring.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/history.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/ico.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/ip_entry.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/khim.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/menuentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/ntext.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/panelframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/plotchart.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/ruler.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/screenruler.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/scrollwin.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/statusbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/style.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/superframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/swaplist.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/tablelist.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/tablelist_core.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/tkpiechart.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/toolbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/tooltip.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/validator.rb1
-rw-r--r--ext/tk/lib/tkextlib/tcllib/widget.rb1
-rw-r--r--ext/tk/lib/tkextlib/tclx.rb1
-rw-r--r--ext/tk/lib/tkextlib/tclx/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tclx/tclx.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/dialog.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/sizegrip.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/style.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tcheckbutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tcombobox.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tentry.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tlabel.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tlabelframe.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tmenubutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tnotebook.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tpaned.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tprogressbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tradiobutton.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/treeview.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tscale.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tscrollbar.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tseparator.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tspinbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/tile/tsquare.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkDND.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkDND/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkDND/shape.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkDND/tkdnd.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkHTML.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkHTML/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/bmp.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/dted.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/gif.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/ico.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/jpeg.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/pcx.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/pixmap.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/png.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/ppm.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/ps.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/raw.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/sgi.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/sun.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/tga.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/tiff.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/window.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/xbm.rb1
-rw-r--r--ext/tk/lib/tkextlib/tkimg/xpm.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktable.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktable/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktable/tktable.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktrans.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktrans/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/tktrans/tktrans.rb1
-rw-r--r--ext/tk/lib/tkextlib/treectrl.rb1
-rw-r--r--ext/tk/lib/tkextlib/treectrl/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/treectrl/tktreectrl.rb1
-rw-r--r--ext/tk/lib/tkextlib/trofs.rb1
-rw-r--r--ext/tk/lib/tkextlib/trofs/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/trofs/trofs.rb1
-rw-r--r--ext/tk/lib/tkextlib/version.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/bargraph.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/charts.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/dial.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/pie.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/vu/spinbox.rb1
-rw-r--r--ext/tk/lib/tkextlib/winico.rb1
-rw-r--r--ext/tk/lib/tkextlib/winico/setup.rb1
-rw-r--r--ext/tk/lib/tkextlib/winico/winico.rb1
-rw-r--r--ext/tk/lib/tkfont.rb1
-rw-r--r--ext/tk/lib/tkmacpkg.rb1
-rw-r--r--ext/tk/lib/tkmenubar.rb1
-rw-r--r--ext/tk/lib/tkmngfocus.rb1
-rw-r--r--ext/tk/lib/tkpalette.rb1
-rw-r--r--ext/tk/lib/tkscrollbox.rb1
-rw-r--r--ext/tk/lib/tktext.rb1
-rw-r--r--ext/tk/lib/tkvirtevent.rb1
-rw-r--r--ext/tk/lib/tkwinpkg.rb1
339 files changed, 339 insertions, 0 deletions
diff --git a/ext/tk/lib/multi-tk.rb b/ext/tk/lib/multi-tk.rb
index e0f41d0f6a5..a5759c70cca 100644
--- a/ext/tk/lib/multi-tk.rb
+++ b/ext/tk/lib/multi-tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# multi-tk.rb - supports multi Tk interpreters
# by Hidetoshi NAGAI <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/remote-tk.rb b/ext/tk/lib/remote-tk.rb
index f4144896458..165e6587fd8 100644
--- a/ext/tk/lib/remote-tk.rb
+++ b/ext/tk/lib/remote-tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# remote-tk.rb - supports to control remote Tk interpreters
# by Hidetoshi NAGAI <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tcltk.rb b/ext/tk/lib/tcltk.rb
index f8fbdfbe6d9..7796bb86ef2 100644
--- a/ext/tk/lib/tcltk.rb
+++ b/ext/tk/lib/tcltk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
# tof
#### tcltk library, more direct manipulation of tcl/tk
diff --git a/ext/tk/lib/tk.rb b/ext/tk/lib/tk.rb
index dd29589e869..7fe2fb08787 100644
--- a/ext/tk/lib/tk.rb
+++ b/ext/tk/lib/tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk.rb - Tk interface module using tcltklib
# by Yukihiro Matsumoto <matz@netlab.jp>
diff --git a/ext/tk/lib/tk/after.rb b/ext/tk/lib/tk/after.rb
index 8c58210331b..3213a6b818c 100644
--- a/ext/tk/lib/tk/after.rb
+++ b/ext/tk/lib/tk/after.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/after.rb : methods for Tcl/Tk after command
#
diff --git a/ext/tk/lib/tk/autoload.rb b/ext/tk/lib/tk/autoload.rb
index 451922c7d32..3d19fb053d7 100644
--- a/ext/tk/lib/tk/autoload.rb
+++ b/ext/tk/lib/tk/autoload.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# autoload
#
diff --git a/ext/tk/lib/tk/bgerror.rb b/ext/tk/lib/tk/bgerror.rb
index c82a8e046b2..9d2f59357e7 100644
--- a/ext/tk/lib/tk/bgerror.rb
+++ b/ext/tk/lib/tk/bgerror.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkbgerror -- bgerror ( tkerror ) module
# 1998/07/16 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/bindtag.rb b/ext/tk/lib/tk/bindtag.rb
index 23b4e0b7c3b..ad3c90b5054 100644
--- a/ext/tk/lib/tk/bindtag.rb
+++ b/ext/tk/lib/tk/bindtag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/bind.rb : control event binding
#
diff --git a/ext/tk/lib/tk/busy.rb b/ext/tk/lib/tk/busy.rb
index 7f4f89f5240..18ebede9ddb 100644
--- a/ext/tk/lib/tk/busy.rb
+++ b/ext/tk/lib/tk/busy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/busy.rb: support 'tk busy' command (Tcl/Tk8.6 or later)
#
diff --git a/ext/tk/lib/tk/button.rb b/ext/tk/lib/tk/button.rb
index 65233c91b60..dc252d8e82b 100644
--- a/ext/tk/lib/tk/button.rb
+++ b/ext/tk/lib/tk/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/button.rb : treat button widget
#
diff --git a/ext/tk/lib/tk/canvas.rb b/ext/tk/lib/tk/canvas.rb
index f3e9a7c229d..d707733d8cf 100644
--- a/ext/tk/lib/tk/canvas.rb
+++ b/ext/tk/lib/tk/canvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/canvas.rb - Tk canvas classes
# by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/canvastag.rb b/ext/tk/lib/tk/canvastag.rb
index 495d92a9a8c..4a14cd78a91 100644
--- a/ext/tk/lib/tk/canvastag.rb
+++ b/ext/tk/lib/tk/canvastag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/canvastag.rb - methods for treating canvas tags
#
diff --git a/ext/tk/lib/tk/checkbutton.rb b/ext/tk/lib/tk/checkbutton.rb
index b7449541c5c..521b015b3e1 100644
--- a/ext/tk/lib/tk/checkbutton.rb
+++ b/ext/tk/lib/tk/checkbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/checkbutton.rb : treat checkbutton widget
#
diff --git a/ext/tk/lib/tk/clipboard.rb b/ext/tk/lib/tk/clipboard.rb
index d4205a5c281..c5f481f979f 100644
--- a/ext/tk/lib/tk/clipboard.rb
+++ b/ext/tk/lib/tk/clipboard.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/clipboard.rb : methods to treat clipboard
#
diff --git a/ext/tk/lib/tk/clock.rb b/ext/tk/lib/tk/clock.rb
index 4e9438f5abe..df900d7364f 100644
--- a/ext/tk/lib/tk/clock.rb
+++ b/ext/tk/lib/tk/clock.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/clock.rb : methods for clock command
#
diff --git a/ext/tk/lib/tk/composite.rb b/ext/tk/lib/tk/composite.rb
index e267c7a22b0..830d383d69c 100644
--- a/ext/tk/lib/tk/composite.rb
+++ b/ext/tk/lib/tk/composite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/composite.rb :
#
diff --git a/ext/tk/lib/tk/console.rb b/ext/tk/lib/tk/console.rb
index 64e257594cc..c560912da81 100644
--- a/ext/tk/lib/tk/console.rb
+++ b/ext/tk/lib/tk/console.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/console.rb : control the console on system without a real console
#
diff --git a/ext/tk/lib/tk/dialog.rb b/ext/tk/lib/tk/dialog.rb
index 7ef78206991..0b19be7cfae 100644
--- a/ext/tk/lib/tk/dialog.rb
+++ b/ext/tk/lib/tk/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/dialog.rb : create dialog boxes
#
diff --git a/ext/tk/lib/tk/encodedstr.rb b/ext/tk/lib/tk/encodedstr.rb
index 59fbb1911da..9ca13b3d1af 100644
--- a/ext/tk/lib/tk/encodedstr.rb
+++ b/ext/tk/lib/tk/encodedstr.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/encodedstr.rb : Tk::EncodedString class
#
diff --git a/ext/tk/lib/tk/entry.rb b/ext/tk/lib/tk/entry.rb
index d4aa03f2b6b..aa40e4755c4 100644
--- a/ext/tk/lib/tk/entry.rb
+++ b/ext/tk/lib/tk/entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/entry.rb - Tk entry classes
# by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/event.rb b/ext/tk/lib/tk/event.rb
index bf4e1223226..5658e92874a 100644
--- a/ext/tk/lib/tk/event.rb
+++ b/ext/tk/lib/tk/event.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/event.rb - module for event
#
diff --git a/ext/tk/lib/tk/font.rb b/ext/tk/lib/tk/font.rb
index 03db850f967..7a2a5498494 100644
--- a/ext/tk/lib/tk/font.rb
+++ b/ext/tk/lib/tk/font.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/font.rb - the class to treat fonts on Ruby/Tk
#
diff --git a/ext/tk/lib/tk/fontchooser.rb b/ext/tk/lib/tk/fontchooser.rb
index 6dab0c6cf99..325ca4dbd2f 100644
--- a/ext/tk/lib/tk/fontchooser.rb
+++ b/ext/tk/lib/tk/fontchooser.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/fontchooser.rb -- "tk fontchooser" support (Tcl/Tk8.6 or later)
#
diff --git a/ext/tk/lib/tk/frame.rb b/ext/tk/lib/tk/frame.rb
index 51189397329..0682faf3fe2 100644
--- a/ext/tk/lib/tk/frame.rb
+++ b/ext/tk/lib/tk/frame.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/frame.rb : treat frame widget
#
diff --git a/ext/tk/lib/tk/grid.rb b/ext/tk/lib/tk/grid.rb
index e1e07c44fa4..5a4a26403a8 100644
--- a/ext/tk/lib/tk/grid.rb
+++ b/ext/tk/lib/tk/grid.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/grid.rb : control grid geometry manager
#
diff --git a/ext/tk/lib/tk/image.rb b/ext/tk/lib/tk/image.rb
index 972383982ff..ec23e495d0e 100644
--- a/ext/tk/lib/tk/image.rb
+++ b/ext/tk/lib/tk/image.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/image.rb : treat Tk image objects
#
diff --git a/ext/tk/lib/tk/itemconfig.rb b/ext/tk/lib/tk/itemconfig.rb
index e8eb83d66c4..e615fa0950f 100644
--- a/ext/tk/lib/tk/itemconfig.rb
+++ b/ext/tk/lib/tk/itemconfig.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/itemconfig.rb : control item/tag configuration of widget
#
diff --git a/ext/tk/lib/tk/itemfont.rb b/ext/tk/lib/tk/itemfont.rb
index b5da4fa1efc..92f75ac3886 100644
--- a/ext/tk/lib/tk/itemfont.rb
+++ b/ext/tk/lib/tk/itemfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/itemfont.rb : control font of widget items
#
diff --git a/ext/tk/lib/tk/kinput.rb b/ext/tk/lib/tk/kinput.rb
index b63f756def6..6d2b3d7a7a1 100644
--- a/ext/tk/lib/tk/kinput.rb
+++ b/ext/tk/lib/tk/kinput.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/kinput.rb : control kinput
#
diff --git a/ext/tk/lib/tk/label.rb b/ext/tk/lib/tk/label.rb
index 05e430e49b2..48f67deb311 100644
--- a/ext/tk/lib/tk/label.rb
+++ b/ext/tk/lib/tk/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/label.rb : treat label widget
#
diff --git a/ext/tk/lib/tk/labelframe.rb b/ext/tk/lib/tk/labelframe.rb
index 6f679e55b50..f9497dc2f07 100644
--- a/ext/tk/lib/tk/labelframe.rb
+++ b/ext/tk/lib/tk/labelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/labelframe.rb : treat labelframe widget
#
diff --git a/ext/tk/lib/tk/listbox.rb b/ext/tk/lib/tk/listbox.rb
index 6742b2132cb..df4d422007c 100644
--- a/ext/tk/lib/tk/listbox.rb
+++ b/ext/tk/lib/tk/listbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/listbox.rb : treat listbox widget
#
diff --git a/ext/tk/lib/tk/macpkg.rb b/ext/tk/lib/tk/macpkg.rb
index 3ca7953c13e..abf9b176fb3 100644
--- a/ext/tk/lib/tk/macpkg.rb
+++ b/ext/tk/lib/tk/macpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/macpkg.rb : methods for Tcl/Tk packages for Macintosh
# 2000/11/22 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/menu.rb b/ext/tk/lib/tk/menu.rb
index bcd250026d9..16347a98eaa 100644
--- a/ext/tk/lib/tk/menu.rb
+++ b/ext/tk/lib/tk/menu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/menu.rb : treat menu and menubutton
#
diff --git a/ext/tk/lib/tk/menubar.rb b/ext/tk/lib/tk/menubar.rb
index 9d5571c4700..17cb4477c99 100644
--- a/ext/tk/lib/tk/menubar.rb
+++ b/ext/tk/lib/tk/menubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/menubar.rb
#
diff --git a/ext/tk/lib/tk/menuspec.rb b/ext/tk/lib/tk/menuspec.rb
index cb3597eec9e..2de62242ff4 100644
--- a/ext/tk/lib/tk/menuspec.rb
+++ b/ext/tk/lib/tk/menuspec.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/menuspec.rb
# Hidethoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tk/message.rb b/ext/tk/lib/tk/message.rb
index 5f73b3066f8..432e9667bd8 100644
--- a/ext/tk/lib/tk/message.rb
+++ b/ext/tk/lib/tk/message.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/message.rb : treat message widget
#
diff --git a/ext/tk/lib/tk/mngfocus.rb b/ext/tk/lib/tk/mngfocus.rb
index a05fb94f8e2..06b20eb6aba 100644
--- a/ext/tk/lib/tk/mngfocus.rb
+++ b/ext/tk/lib/tk/mngfocus.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/mngfocus.rb : methods for Tcl/Tk standard library 'focus.tcl'
# by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/msgcat.rb b/ext/tk/lib/tk/msgcat.rb
index f2d0653c69a..1e98889faf7 100644
--- a/ext/tk/lib/tk/msgcat.rb
+++ b/ext/tk/lib/tk/msgcat.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/msgcat.rb : methods for Tcl message catalog
# by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/namespace.rb b/ext/tk/lib/tk/namespace.rb
index 0119ba5ef77..1cab6fa0601 100644
--- a/ext/tk/lib/tk/namespace.rb
+++ b/ext/tk/lib/tk/namespace.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/namespace.rb : methods to manipulate Tcl/Tk namespace
# by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/optiondb.rb b/ext/tk/lib/tk/optiondb.rb
index 91d2697a863..b27a5e5721e 100644
--- a/ext/tk/lib/tk/optiondb.rb
+++ b/ext/tk/lib/tk/optiondb.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/optiondb.rb : treat option database
#
diff --git a/ext/tk/lib/tk/optionobj.rb b/ext/tk/lib/tk/optionobj.rb
index 29b06da0eb1..4219e4be716 100644
--- a/ext/tk/lib/tk/optionobj.rb
+++ b/ext/tk/lib/tk/optionobj.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/optionobj.rb : control options for a group of widgets
#
diff --git a/ext/tk/lib/tk/pack.rb b/ext/tk/lib/tk/pack.rb
index 220a38e524a..45926d4043b 100644
--- a/ext/tk/lib/tk/pack.rb
+++ b/ext/tk/lib/tk/pack.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/pack.rb : control pack geometry manager
#
diff --git a/ext/tk/lib/tk/package.rb b/ext/tk/lib/tk/package.rb
index 0c329732f52..fe6939c2d4d 100644
--- a/ext/tk/lib/tk/package.rb
+++ b/ext/tk/lib/tk/package.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/package.rb : package command
#
diff --git a/ext/tk/lib/tk/palette.rb b/ext/tk/lib/tk/palette.rb
index 9462bb06674..e118e8dbe5a 100644
--- a/ext/tk/lib/tk/palette.rb
+++ b/ext/tk/lib/tk/palette.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/palette.rb : methods for Tcl/Tk standard library 'palette.tcl'
# 1998/06/21 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/panedwindow.rb b/ext/tk/lib/tk/panedwindow.rb
index 04407802ea6..285292f0182 100644
--- a/ext/tk/lib/tk/panedwindow.rb
+++ b/ext/tk/lib/tk/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/panedwindow.rb : treat panedwindow
#
diff --git a/ext/tk/lib/tk/place.rb b/ext/tk/lib/tk/place.rb
index 109d866fdac..efda36df5ee 100644
--- a/ext/tk/lib/tk/place.rb
+++ b/ext/tk/lib/tk/place.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/place.rb : control place geometry manager
#
diff --git a/ext/tk/lib/tk/radiobutton.rb b/ext/tk/lib/tk/radiobutton.rb
index 627df6d9cf2..b0858df2b43 100644
--- a/ext/tk/lib/tk/radiobutton.rb
+++ b/ext/tk/lib/tk/radiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/radiobutton.rb : treat radiobutton widget
#
diff --git a/ext/tk/lib/tk/root.rb b/ext/tk/lib/tk/root.rb
index b4f0bd107f0..3fb7c472d3d 100644
--- a/ext/tk/lib/tk/root.rb
+++ b/ext/tk/lib/tk/root.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/root.rb : treat root widget
#
diff --git a/ext/tk/lib/tk/scale.rb b/ext/tk/lib/tk/scale.rb
index 0bdcead7f27..f6f60e3c258 100644
--- a/ext/tk/lib/tk/scale.rb
+++ b/ext/tk/lib/tk/scale.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/scale.rb : treat scale widget
#
diff --git a/ext/tk/lib/tk/scrollable.rb b/ext/tk/lib/tk/scrollable.rb
index 96959b7a4bb..e9b4a93d6dd 100644
--- a/ext/tk/lib/tk/scrollable.rb
+++ b/ext/tk/lib/tk/scrollable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/scrollable.rb : module for scrollable widget
#
diff --git a/ext/tk/lib/tk/scrollbar.rb b/ext/tk/lib/tk/scrollbar.rb
index c0ac201acbe..c16ed38756e 100644
--- a/ext/tk/lib/tk/scrollbar.rb
+++ b/ext/tk/lib/tk/scrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/scrollbar.rb : treat scrollbar widget
#
diff --git a/ext/tk/lib/tk/scrollbox.rb b/ext/tk/lib/tk/scrollbox.rb
index d20742a6660..a470765d7ce 100644
--- a/ext/tk/lib/tk/scrollbox.rb
+++ b/ext/tk/lib/tk/scrollbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/scrollbox.rb - Tk Listbox with Scrollbar
# as an example of Composite Widget
diff --git a/ext/tk/lib/tk/selection.rb b/ext/tk/lib/tk/selection.rb
index ba0a6f49f90..085d8b2d2d3 100644
--- a/ext/tk/lib/tk/selection.rb
+++ b/ext/tk/lib/tk/selection.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/selection.rb : control selection
#
diff --git a/ext/tk/lib/tk/spinbox.rb b/ext/tk/lib/tk/spinbox.rb
index f2917d60caa..4be41c4266d 100644
--- a/ext/tk/lib/tk/spinbox.rb
+++ b/ext/tk/lib/tk/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/spinbox.rb - Tk spinbox classes
# by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/tagfont.rb b/ext/tk/lib/tk/tagfont.rb
index a1807395d24..e3fd60465c7 100644
--- a/ext/tk/lib/tk/tagfont.rb
+++ b/ext/tk/lib/tk/tagfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/tagfont.rb : control font of tags
#
diff --git a/ext/tk/lib/tk/text.rb b/ext/tk/lib/tk/text.rb
index c18b3843b40..fc4f1129336 100644
--- a/ext/tk/lib/tk/text.rb
+++ b/ext/tk/lib/tk/text.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/text.rb - Tk text classes
# by Yukihiro Matsumoto <matz@caelum.co.jp>
diff --git a/ext/tk/lib/tk/textimage.rb b/ext/tk/lib/tk/textimage.rb
index 99027a06fb6..f7329c5dcc8 100644
--- a/ext/tk/lib/tk/textimage.rb
+++ b/ext/tk/lib/tk/textimage.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/textimage.rb - treat Tk text image object
#
diff --git a/ext/tk/lib/tk/textmark.rb b/ext/tk/lib/tk/textmark.rb
index d1888c5e543..80945cc70cb 100644
--- a/ext/tk/lib/tk/textmark.rb
+++ b/ext/tk/lib/tk/textmark.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/textmark.rb - methods for treating text marks
#
diff --git a/ext/tk/lib/tk/texttag.rb b/ext/tk/lib/tk/texttag.rb
index 96692014e47..9f11c6539bd 100644
--- a/ext/tk/lib/tk/texttag.rb
+++ b/ext/tk/lib/tk/texttag.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/texttag.rb - methods for treating text tags
#
diff --git a/ext/tk/lib/tk/textwindow.rb b/ext/tk/lib/tk/textwindow.rb
index 49327b2c812..e0be5bac7a5 100644
--- a/ext/tk/lib/tk/textwindow.rb
+++ b/ext/tk/lib/tk/textwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/textwindow.rb - treat Tk text window object
#
diff --git a/ext/tk/lib/tk/timer.rb b/ext/tk/lib/tk/timer.rb
index 29aa84b0d9a..794463aab11 100644
--- a/ext/tk/lib/tk/timer.rb
+++ b/ext/tk/lib/tk/timer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/timer.rb : methods for Tcl/Tk after command
#
diff --git a/ext/tk/lib/tk/tk_mac.rb b/ext/tk/lib/tk/tk_mac.rb
index 77bb2349cce..ed90fd1c677 100644
--- a/ext/tk/lib/tk/tk_mac.rb
+++ b/ext/tk/lib/tk/tk_mac.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/tk_mac.rb : Access Mac-Specific functionality on OS X from Tk
# (supported by Tk8.6 or later)
diff --git a/ext/tk/lib/tk/toplevel.rb b/ext/tk/lib/tk/toplevel.rb
index 30ef009517d..e66b0fc1be2 100644
--- a/ext/tk/lib/tk/toplevel.rb
+++ b/ext/tk/lib/tk/toplevel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/toplevel.rb : treat toplevel widget
#
diff --git a/ext/tk/lib/tk/ttk_selector.rb b/ext/tk/lib/tk/ttk_selector.rb
index cc9e9928cba..4589e7fc29a 100644
--- a/ext/tk/lib/tk/ttk_selector.rb
+++ b/ext/tk/lib/tk/ttk_selector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ttk_selector
#
diff --git a/ext/tk/lib/tk/txtwin_abst.rb b/ext/tk/lib/tk/txtwin_abst.rb
index 540f806d17d..3c9beef6c46 100644
--- a/ext/tk/lib/tk/txtwin_abst.rb
+++ b/ext/tk/lib/tk/txtwin_abst.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/txtwin_abst.rb : TkTextWin abstruct class
#
diff --git a/ext/tk/lib/tk/validation.rb b/ext/tk/lib/tk/validation.rb
index 0ebd5c51b73..c6cbfb280ed 100644
--- a/ext/tk/lib/tk/validation.rb
+++ b/ext/tk/lib/tk/validation.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/validation.rb - validation support module for entry, spinbox, and so on
#
diff --git a/ext/tk/lib/tk/variable.rb b/ext/tk/lib/tk/variable.rb
index 496225a92d9..8ac0fc6ace2 100644
--- a/ext/tk/lib/tk/variable.rb
+++ b/ext/tk/lib/tk/variable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/variable.rb : treat Tk variable object
#
diff --git a/ext/tk/lib/tk/virtevent.rb b/ext/tk/lib/tk/virtevent.rb
index c11e9692e70..de3c33da363 100644
--- a/ext/tk/lib/tk/virtevent.rb
+++ b/ext/tk/lib/tk/virtevent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/virtevent.rb : treats virtual events
# 1998/07/16 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/winfo.rb b/ext/tk/lib/tk/winfo.rb
index b10cfe6760f..36f32e59526 100644
--- a/ext/tk/lib/tk/winfo.rb
+++ b/ext/tk/lib/tk/winfo.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/winfo.rb : methods for winfo command
#
diff --git a/ext/tk/lib/tk/winpkg.rb b/ext/tk/lib/tk/winpkg.rb
index 80e0439acec..2a8f724bef4 100644
--- a/ext/tk/lib/tk/winpkg.rb
+++ b/ext/tk/lib/tk/winpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/winpkg.rb : methods for Tcl/Tk packages for Microsoft Windows
# 2000/11/22 by Hidetoshi Nagai <nagai@ai.kyutech.ac.jp>
diff --git a/ext/tk/lib/tk/wm.rb b/ext/tk/lib/tk/wm.rb
index fcd5a2cbd28..114ba242763 100644
--- a/ext/tk/lib/tk/wm.rb
+++ b/ext/tk/lib/tk/wm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/wm.rb : methods for wm command
#
diff --git a/ext/tk/lib/tk/xim.rb b/ext/tk/lib/tk/xim.rb
index c0126c51750..7e77591b459 100644
--- a/ext/tk/lib/tk/xim.rb
+++ b/ext/tk/lib/tk/xim.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tk/xim.rb : control imput_method
#
diff --git a/ext/tk/lib/tkafter.rb b/ext/tk/lib/tkafter.rb
index f65945884ca..0ce5049d4aa 100644
--- a/ext/tk/lib/tkafter.rb
+++ b/ext/tk/lib/tkafter.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkafter.rb - load tk/after.rb
#
diff --git a/ext/tk/lib/tkbgerror.rb b/ext/tk/lib/tkbgerror.rb
index deba7a57fa9..875f3fef2fc 100644
--- a/ext/tk/lib/tkbgerror.rb
+++ b/ext/tk/lib/tkbgerror.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkbgerror.rb - load tk/bgerror.rb
#
diff --git a/ext/tk/lib/tkcanvas.rb b/ext/tk/lib/tkcanvas.rb
index 9524614291f..d4d0afac9e2 100644
--- a/ext/tk/lib/tkcanvas.rb
+++ b/ext/tk/lib/tkcanvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkcanvas.rb - load tk/canvas.rb
#
diff --git a/ext/tk/lib/tkclass.rb b/ext/tk/lib/tkclass.rb
index 87f5acc453d..947cbf3a4a9 100644
--- a/ext/tk/lib/tkclass.rb
+++ b/ext/tk/lib/tkclass.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkclass.rb - Tk classes
# Date: 2000/11/27 09:23:36
diff --git a/ext/tk/lib/tkconsole.rb b/ext/tk/lib/tkconsole.rb
index 9960ddb8ac1..f4e8669c11a 100644
--- a/ext/tk/lib/tkconsole.rb
+++ b/ext/tk/lib/tkconsole.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkconsole.rb - load tk/console.rb
#
diff --git a/ext/tk/lib/tkdialog.rb b/ext/tk/lib/tkdialog.rb
index bec5e5d29a1..7a24e2a37a6 100644
--- a/ext/tk/lib/tkdialog.rb
+++ b/ext/tk/lib/tkdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkdialog.rb - load tk/dialog.rb
#
diff --git a/ext/tk/lib/tkentry.rb b/ext/tk/lib/tkentry.rb
index 2dcfcab5dab..9ae2f7c8fea 100644
--- a/ext/tk/lib/tkentry.rb
+++ b/ext/tk/lib/tkentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkentry.rb - load tk/entry.rb
#
diff --git a/ext/tk/lib/tkextlib/ICONS.rb b/ext/tk/lib/tkextlib/ICONS.rb
index 18d84c05e9c..10402c12926 100644
--- a/ext/tk/lib/tkextlib/ICONS.rb
+++ b/ext/tk/lib/tkextlib/ICONS.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ICONS support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/ICONS/icons.rb b/ext/tk/lib/tkextlib/ICONS/icons.rb
index bd3180aa555..2934757b6df 100644
--- a/ext/tk/lib/tkextlib/ICONS/icons.rb
+++ b/ext/tk/lib/tkextlib/ICONS/icons.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/ICONS/icons.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/ICONS/setup.rb b/ext/tk/lib/tkextlib/ICONS/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/ICONS/setup.rb
+++ b/ext/tk/lib/tkextlib/ICONS/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/blt.rb b/ext/tk/lib/tkextlib/blt.rb
index 8b132e41a7f..665e41226f6 100644
--- a/ext/tk/lib/tkextlib/blt.rb
+++ b/ext/tk/lib/tkextlib/blt.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# BLT support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/barchart.rb b/ext/tk/lib/tkextlib/blt/barchart.rb
index a86b91c959f..5b6f09ead33 100644
--- a/ext/tk/lib/tkextlib/blt/barchart.rb
+++ b/ext/tk/lib/tkextlib/blt/barchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/barchart.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/bitmap.rb b/ext/tk/lib/tkextlib/blt/bitmap.rb
index 3254b63116f..b9f411044e9 100644
--- a/ext/tk/lib/tkextlib/blt/bitmap.rb
+++ b/ext/tk/lib/tkextlib/blt/bitmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/bitmap.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/busy.rb b/ext/tk/lib/tkextlib/blt/busy.rb
index b5287fb5b73..ab24420750d 100644
--- a/ext/tk/lib/tkextlib/blt/busy.rb
+++ b/ext/tk/lib/tkextlib/blt/busy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/busy.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/component.rb b/ext/tk/lib/tkextlib/blt/component.rb
index c7ea213cee8..a6b6f139050 100644
--- a/ext/tk/lib/tkextlib/blt/component.rb
+++ b/ext/tk/lib/tkextlib/blt/component.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/component.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/container.rb b/ext/tk/lib/tkextlib/blt/container.rb
index be05828d952..6ee11138d73 100644
--- a/ext/tk/lib/tkextlib/blt/container.rb
+++ b/ext/tk/lib/tkextlib/blt/container.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/container.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/cutbuffer.rb b/ext/tk/lib/tkextlib/blt/cutbuffer.rb
index 1cc39dfb94a..b36aece6e7e 100644
--- a/ext/tk/lib/tkextlib/blt/cutbuffer.rb
+++ b/ext/tk/lib/tkextlib/blt/cutbuffer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/cutbuffer.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/dragdrop.rb b/ext/tk/lib/tkextlib/blt/dragdrop.rb
index aa5c5654c2c..dc2531b12e4 100644
--- a/ext/tk/lib/tkextlib/blt/dragdrop.rb
+++ b/ext/tk/lib/tkextlib/blt/dragdrop.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/dragdrop.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/eps.rb b/ext/tk/lib/tkextlib/blt/eps.rb
index 0dba87a7cce..bd2d3cc47e2 100644
--- a/ext/tk/lib/tkextlib/blt/eps.rb
+++ b/ext/tk/lib/tkextlib/blt/eps.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/eps.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/graph.rb b/ext/tk/lib/tkextlib/blt/graph.rb
index 6bd44240653..02de006f338 100644
--- a/ext/tk/lib/tkextlib/blt/graph.rb
+++ b/ext/tk/lib/tkextlib/blt/graph.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/graph.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/htext.rb b/ext/tk/lib/tkextlib/blt/htext.rb
index 878bd9982d5..d0f5e8b5e6d 100644
--- a/ext/tk/lib/tkextlib/blt/htext.rb
+++ b/ext/tk/lib/tkextlib/blt/htext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/htext.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/setup.rb b/ext/tk/lib/tkextlib/blt/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/blt/setup.rb
+++ b/ext/tk/lib/tkextlib/blt/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/blt/spline.rb b/ext/tk/lib/tkextlib/blt/spline.rb
index 9f75a0b2177..84d96a08f0f 100644
--- a/ext/tk/lib/tkextlib/blt/spline.rb
+++ b/ext/tk/lib/tkextlib/blt/spline.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/spline.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/stripchart.rb b/ext/tk/lib/tkextlib/blt/stripchart.rb
index 74093f18684..332521ab0bf 100644
--- a/ext/tk/lib/tkextlib/blt/stripchart.rb
+++ b/ext/tk/lib/tkextlib/blt/stripchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/stripchart.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/table.rb b/ext/tk/lib/tkextlib/blt/table.rb
index 205e29e6c57..39e345408d3 100644
--- a/ext/tk/lib/tkextlib/blt/table.rb
+++ b/ext/tk/lib/tkextlib/blt/table.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/table.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tabnotebook.rb b/ext/tk/lib/tkextlib/blt/tabnotebook.rb
index 82936c67d3e..f08f1981636 100644
--- a/ext/tk/lib/tkextlib/blt/tabnotebook.rb
+++ b/ext/tk/lib/tkextlib/blt/tabnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tabnotebook.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tabset.rb b/ext/tk/lib/tkextlib/blt/tabset.rb
index c4716c7304f..022d9784e96 100644
--- a/ext/tk/lib/tkextlib/blt/tabset.rb
+++ b/ext/tk/lib/tkextlib/blt/tabset.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tabset.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/ted.rb b/ext/tk/lib/tkextlib/blt/ted.rb
index 53ab9acdaa3..7e81eab27d3 100644
--- a/ext/tk/lib/tkextlib/blt/ted.rb
+++ b/ext/tk/lib/tkextlib/blt/ted.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/ted.rb
#
diff --git a/ext/tk/lib/tkextlib/blt/tile.rb b/ext/tk/lib/tkextlib/blt/tile.rb
index c67cafd8d63..f52a5d39440 100644
--- a/ext/tk/lib/tkextlib/blt/tile.rb
+++ b/ext/tk/lib/tkextlib/blt/tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/button.rb b/ext/tk/lib/tkextlib/blt/tile/button.rb
index 2e0863cfbe3..e3d819edb74 100644
--- a/ext/tk/lib/tkextlib/blt/tile/button.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/button.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb b/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
index da230b59257..0c8c7f9774c 100644
--- a/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/checkbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/checkbutton.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/frame.rb b/ext/tk/lib/tkextlib/blt/tile/frame.rb
index 5434af4b72b..8d979fe485b 100644
--- a/ext/tk/lib/tkextlib/blt/tile/frame.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/frame.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/frame.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/label.rb b/ext/tk/lib/tkextlib/blt/tile/label.rb
index f370c1403b9..f58450d9027 100644
--- a/ext/tk/lib/tkextlib/blt/tile/label.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/label.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb b/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
index 814f9a5cc4a..ee449c75b0a 100644
--- a/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/radiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/radiobutton.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb b/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
index 2ae871d518c..35d878d5aa6 100644
--- a/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/scrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/scrollbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tile/toplevel.rb b/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
index 76d5f86b1b5..e30b8b37b51 100644
--- a/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
+++ b/ext/tk/lib/tkextlib/blt/tile/toplevel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tile/toplevel.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/tree.rb b/ext/tk/lib/tkextlib/blt/tree.rb
index 1a3563e60d0..6c84ef78a6e 100644
--- a/ext/tk/lib/tkextlib/blt/tree.rb
+++ b/ext/tk/lib/tkextlib/blt/tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/tree.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/treeview.rb b/ext/tk/lib/tkextlib/blt/treeview.rb
index 38d90412e0f..2866ba30270 100644
--- a/ext/tk/lib/tkextlib/blt/treeview.rb
+++ b/ext/tk/lib/tkextlib/blt/treeview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/treeview.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/unix_dnd.rb b/ext/tk/lib/tkextlib/blt/unix_dnd.rb
index 8996f7c8917..3c0cd33b79c 100644
--- a/ext/tk/lib/tkextlib/blt/unix_dnd.rb
+++ b/ext/tk/lib/tkextlib/blt/unix_dnd.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/unix_dnd.rb
#
diff --git a/ext/tk/lib/tkextlib/blt/vector.rb b/ext/tk/lib/tkextlib/blt/vector.rb
index 742e901d3e4..a3ab7e64b2b 100644
--- a/ext/tk/lib/tkextlib/blt/vector.rb
+++ b/ext/tk/lib/tkextlib/blt/vector.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/vector.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/watch.rb b/ext/tk/lib/tkextlib/blt/watch.rb
index 292623ff583..b88c81c7458 100644
--- a/ext/tk/lib/tkextlib/blt/watch.rb
+++ b/ext/tk/lib/tkextlib/blt/watch.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/watch.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/blt/win_printer.rb b/ext/tk/lib/tkextlib/blt/win_printer.rb
index 7ac6a0dcfc0..8d609acc190 100644
--- a/ext/tk/lib/tkextlib/blt/win_printer.rb
+++ b/ext/tk/lib/tkextlib/blt/win_printer.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/win_printer.rb
#
diff --git a/ext/tk/lib/tkextlib/blt/winop.rb b/ext/tk/lib/tkextlib/blt/winop.rb
index 03bdb608105..38033e11132 100644
--- a/ext/tk/lib/tkextlib/blt/winop.rb
+++ b/ext/tk/lib/tkextlib/blt/winop.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/blt/winop.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget.rb b/ext/tk/lib/tkextlib/bwidget.rb
index 7a1eff51d88..0fa9c77ecfd 100644
--- a/ext/tk/lib/tkextlib/bwidget.rb
+++ b/ext/tk/lib/tkextlib/bwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# BWidget extension support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb b/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
index 13fe9e59bff..a991245065a 100644
--- a/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
+++ b/ext/tk/lib/tkextlib/bwidget/arrowbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/arrowbutton.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/bitmap.rb b/ext/tk/lib/tkextlib/bwidget/bitmap.rb
index 6cfde203e8a..3acdfdf5ec7 100644
--- a/ext/tk/lib/tkextlib/bwidget/bitmap.rb
+++ b/ext/tk/lib/tkextlib/bwidget/bitmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/bitmap.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/button.rb b/ext/tk/lib/tkextlib/bwidget/button.rb
index e139fb67087..ad880ebfddb 100644
--- a/ext/tk/lib/tkextlib/bwidget/button.rb
+++ b/ext/tk/lib/tkextlib/bwidget/button.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/button.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/buttonbox.rb b/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
index a6de33c40ce..780a6a649e8 100644
--- a/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/buttonbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/buttonbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/combobox.rb b/ext/tk/lib/tkextlib/bwidget/combobox.rb
index 16143dfbc6e..b3de3186d64 100644
--- a/ext/tk/lib/tkextlib/bwidget/combobox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/combobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/combobox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dialog.rb b/ext/tk/lib/tkextlib/bwidget/dialog.rb
index 3b0656f0214..ed929cb830f 100644
--- a/ext/tk/lib/tkextlib/bwidget/dialog.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/dialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dragsite.rb b/ext/tk/lib/tkextlib/bwidget/dragsite.rb
index 4d4de1780cf..6c7ea4491ad 100644
--- a/ext/tk/lib/tkextlib/bwidget/dragsite.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dragsite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/dragsite.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dropsite.rb b/ext/tk/lib/tkextlib/bwidget/dropsite.rb
index e5e98fbc51d..e5eb7f4a880 100644
--- a/ext/tk/lib/tkextlib/bwidget/dropsite.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dropsite.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/dropsite.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb b/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
index 846e58062dd..7e7538fc00e 100644
--- a/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
+++ b/ext/tk/lib/tkextlib/bwidget/dynamichelp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/dynamichelp.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/entry.rb b/ext/tk/lib/tkextlib/bwidget/entry.rb
index 8dc44961238..bfbe2f1967d 100644
--- a/ext/tk/lib/tkextlib/bwidget/entry.rb
+++ b/ext/tk/lib/tkextlib/bwidget/entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/entry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/label.rb b/ext/tk/lib/tkextlib/bwidget/label.rb
index e8d9352c627..9a0b73d95ce 100644
--- a/ext/tk/lib/tkextlib/bwidget/label.rb
+++ b/ext/tk/lib/tkextlib/bwidget/label.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/label.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/labelentry.rb b/ext/tk/lib/tkextlib/bwidget/labelentry.rb
index 16e7b469330..501f9515fa8 100644
--- a/ext/tk/lib/tkextlib/bwidget/labelentry.rb
+++ b/ext/tk/lib/tkextlib/bwidget/labelentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/labelentry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/labelframe.rb b/ext/tk/lib/tkextlib/bwidget/labelframe.rb
index 0710f213f03..21c529c6c98 100644
--- a/ext/tk/lib/tkextlib/bwidget/labelframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/labelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/labelframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/listbox.rb b/ext/tk/lib/tkextlib/bwidget/listbox.rb
index 930491c869b..394c379a343 100644
--- a/ext/tk/lib/tkextlib/bwidget/listbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/listbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/listbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/mainframe.rb b/ext/tk/lib/tkextlib/bwidget/mainframe.rb
index 92253bd8d3d..ad097439c30 100644
--- a/ext/tk/lib/tkextlib/bwidget/mainframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/mainframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/mainframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
index 7b626147370..69819360a85 100644
--- a/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/messagedlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/messagedlg.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/notebook.rb b/ext/tk/lib/tkextlib/bwidget/notebook.rb
index ed28bcd86ac..05c8939a30d 100644
--- a/ext/tk/lib/tkextlib/bwidget/notebook.rb
+++ b/ext/tk/lib/tkextlib/bwidget/notebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/notebook.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb b/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
index 31bbf1fb8bc..ce18ee0edbc 100644
--- a/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
+++ b/ext/tk/lib/tkextlib/bwidget/pagesmanager.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/pagesmanager.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/panedwindow.rb b/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
index 54cf06cbde3..560c5634790 100644
--- a/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
+++ b/ext/tk/lib/tkextlib/bwidget/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/panedwindow.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/panelframe.rb b/ext/tk/lib/tkextlib/bwidget/panelframe.rb
index 1cbf9144250..0e32f4e2617 100644
--- a/ext/tk/lib/tkextlib/bwidget/panelframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/panelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/panelframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/passwddlg.rb b/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
index ea50c87cef0..9fe6fc6a02e 100644
--- a/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/passwddlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/passwddlg.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/progressbar.rb b/ext/tk/lib/tkextlib/bwidget/progressbar.rb
index 18eb67349b7..f06ddc164e6 100644
--- a/ext/tk/lib/tkextlib/bwidget/progressbar.rb
+++ b/ext/tk/lib/tkextlib/bwidget/progressbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/progressbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/progressdlg.rb b/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
index 0c0c4540bce..e11a73e88d1 100644
--- a/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
+++ b/ext/tk/lib/tkextlib/bwidget/progressdlg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/progressdlg.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb b/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
index 5bd00d68706..2b184746a4a 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrollableframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/scrollableframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb b/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
index ea5a18cc66c..9bd5e87554b 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrolledwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/scrolledwindow.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/scrollview.rb b/ext/tk/lib/tkextlib/bwidget/scrollview.rb
index ab27bc91cff..d60fdca89ec 100644
--- a/ext/tk/lib/tkextlib/bwidget/scrollview.rb
+++ b/ext/tk/lib/tkextlib/bwidget/scrollview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/scrollview.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/selectcolor.rb b/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
index 456175e87e9..85809b69bdc 100644
--- a/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
+++ b/ext/tk/lib/tkextlib/bwidget/selectcolor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/selectcolor.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/selectfont.rb b/ext/tk/lib/tkextlib/bwidget/selectfont.rb
index 23419cb0fa1..4f67a2e2396 100644
--- a/ext/tk/lib/tkextlib/bwidget/selectfont.rb
+++ b/ext/tk/lib/tkextlib/bwidget/selectfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/selectfont.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/separator.rb b/ext/tk/lib/tkextlib/bwidget/separator.rb
index 6d92321210e..786c41c7630 100644
--- a/ext/tk/lib/tkextlib/bwidget/separator.rb
+++ b/ext/tk/lib/tkextlib/bwidget/separator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/separator.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/setup.rb b/ext/tk/lib/tkextlib/bwidget/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/bwidget/setup.rb
+++ b/ext/tk/lib/tkextlib/bwidget/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/bwidget/spinbox.rb b/ext/tk/lib/tkextlib/bwidget/spinbox.rb
index 0a45b045fb0..00fe33da39e 100644
--- a/ext/tk/lib/tkextlib/bwidget/spinbox.rb
+++ b/ext/tk/lib/tkextlib/bwidget/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/entry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/statusbar.rb b/ext/tk/lib/tkextlib/bwidget/statusbar.rb
index 5c5dd43fe46..28fd6fab21a 100644
--- a/ext/tk/lib/tkextlib/bwidget/statusbar.rb
+++ b/ext/tk/lib/tkextlib/bwidget/statusbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/statusbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/titleframe.rb b/ext/tk/lib/tkextlib/bwidget/titleframe.rb
index 71879111c19..eca622399ed 100644
--- a/ext/tk/lib/tkextlib/bwidget/titleframe.rb
+++ b/ext/tk/lib/tkextlib/bwidget/titleframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/titleframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/tree.rb b/ext/tk/lib/tkextlib/bwidget/tree.rb
index 089c482fe80..688ed5f324f 100644
--- a/ext/tk/lib/tkextlib/bwidget/tree.rb
+++ b/ext/tk/lib/tkextlib/bwidget/tree.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/tree.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/bwidget/widget.rb b/ext/tk/lib/tkextlib/bwidget/widget.rb
index a93364b5676..ab08826b192 100644
--- a/ext/tk/lib/tkextlib/bwidget/widget.rb
+++ b/ext/tk/lib/tkextlib/bwidget/widget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/bwidget/widget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl.rb b/ext/tk/lib/tkextlib/itcl.rb
index 1d6ecf04f2f..3a67b3f651d 100644
--- a/ext/tk/lib/tkextlib/itcl.rb
+++ b/ext/tk/lib/tkextlib/itcl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# [incr Tcl] support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl/incr_tcl.rb b/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
index 8f6bb33abe0..de1be123920 100644
--- a/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
+++ b/ext/tk/lib/tkextlib/itcl/incr_tcl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/itk/incr_tcl.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itcl/setup.rb b/ext/tk/lib/tkextlib/itcl/setup.rb
index 70b38e49168..917b8779475 100644
--- a/ext/tk/lib/tkextlib/itcl/setup.rb
+++ b/ext/tk/lib/tkextlib/itcl/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/itk.rb b/ext/tk/lib/tkextlib/itk.rb
index 7492bd3eb48..112cb789f2a 100644
--- a/ext/tk/lib/tkextlib/itk.rb
+++ b/ext/tk/lib/tkextlib/itk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# [incr Tk] support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itk/incr_tk.rb b/ext/tk/lib/tkextlib/itk/incr_tk.rb
index 989585e33b0..8c6fe1374f8 100644
--- a/ext/tk/lib/tkextlib/itk/incr_tk.rb
+++ b/ext/tk/lib/tkextlib/itk/incr_tk.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/itk/incr_tk.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/itk/setup.rb b/ext/tk/lib/tkextlib/itk/setup.rb
index 544926efe0a..f32d5d6a755 100644
--- a/ext/tk/lib/tkextlib/itk/setup.rb
+++ b/ext/tk/lib/tkextlib/itk/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/iwidgets.rb b/ext/tk/lib/tkextlib/iwidgets.rb
index ebd4cf7507e..2ebd9d993e4 100644
--- a/ext/tk/lib/tkextlib/iwidgets.rb
+++ b/ext/tk/lib/tkextlib/iwidgets.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# [incr Widgets] support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb b/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
index 91e06d1b525..0357114c839 100644
--- a/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/buttonbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/buttonbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/calendar.rb b/ext/tk/lib/tkextlib/iwidgets/calendar.rb
index a5478c7cc60..4cfb9203c85 100644
--- a/ext/tk/lib/tkextlib/iwidgets/calendar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/calendar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/calendar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb b/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
index 398eec3f1a6..3fe489dc956 100644
--- a/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/canvasprintbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/canvasprintbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb b/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
index e64d8154ca5..4b5fdf5d7c6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/canvasprintdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/canvasprintdialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/checkbox.rb b/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
index a7476c824e5..4589fe7ffa1 100644
--- a/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/checkbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/checkbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/combobox.rb b/ext/tk/lib/tkextlib/iwidgets/combobox.rb
index 82dcf25d0b3..d4c05b5be5d 100644
--- a/ext/tk/lib/tkextlib/iwidgets/combobox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/combobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/combobox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dateentry.rb b/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
index 98a0051e55b..e135b89ed75 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dateentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/dateentry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/datefield.rb b/ext/tk/lib/tkextlib/iwidgets/datefield.rb
index 50d5405a3b8..35977e1f6da 100644
--- a/ext/tk/lib/tkextlib/iwidgets/datefield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/datefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/datefield.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dialog.rb b/ext/tk/lib/tkextlib/iwidgets/dialog.rb
index 2d554ca7b57..edefba18446 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/dialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb b/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
index e8805945320..009fc61c569 100644
--- a/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/dialogshell.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/dialogshell.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb b/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
index 07ab025cdff..3ae3f319b6f 100644
--- a/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/disjointlistbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/disjointlistbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/entryfield.rb b/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
index 3e7149a662c..75baca05d4c 100644
--- a/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/entryfield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/entryfield.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extbutton.rb b/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
index e744fba91a0..3c77c2ec210 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/extbutton.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
index 2ff15bb509d..45817713090 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extfileselectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/extfileselectionbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
index 509fdcf6360..32a06cc46fc 100644
--- a/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/extfileselectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/extfileselectiondialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/feedback.rb b/ext/tk/lib/tkextlib/iwidgets/feedback.rb
index 29d04c8a5d0..e52d60edac8 100644
--- a/ext/tk/lib/tkextlib/iwidgets/feedback.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/feedback.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/feedback.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
index a425b53b5f5..3811f2b57e7 100644
--- a/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/fileselectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/fileselectionbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
index ebcdaf8c0b1..8d368486eaa 100644
--- a/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/fileselectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/fileselectiondialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/finddialog.rb b/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
index 3d522e07c83..ff0b587390d 100644
--- a/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/finddialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/finddialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb b/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
index cb9301d0c91..af999732402 100644
--- a/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/hierarchy.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/hierarchy.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb b/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
index d4ea1aac658..1650c7af375 100644
--- a/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/hyperhelp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/hyperhelp.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb b/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
index 65953984270..f4f37865288 100644
--- a/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/labeledframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/labeledframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb b/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
index d36d42878da..fe3c03135c6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/labeledwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/labeledwidget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb b/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
index ebf48021db9..34c9eb52e3a 100644
--- a/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/mainwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/mainwindow.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/menubar.rb b/ext/tk/lib/tkextlib/iwidgets/menubar.rb
index f9a17d0b550..f7295112300 100644
--- a/ext/tk/lib/tkextlib/iwidgets/menubar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/menubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/menubar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/messagebox.rb b/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
index 6adb53d9418..a4c28228eef 100644
--- a/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/messagebox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/messagebox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb b/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
index 9aa590056f0..2fb4533b671 100644
--- a/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/messagedialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/messagedialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/notebook.rb b/ext/tk/lib/tkextlib/iwidgets/notebook.rb
index 7ed4126a4df..ad2a3725127 100644
--- a/ext/tk/lib/tkextlib/iwidgets/notebook.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/notebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/notebook.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb b/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
index 57a3cc7d2b1..642db11ff13 100644
--- a/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/optionmenu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/optionmenu.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb b/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
index 65463cc85a2..5f17bdd8620 100644
--- a/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/panedwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/panedwindow.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb b/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
index 7c7ff7ad626..fc73a51742b 100644
--- a/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/promptdialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/promptdialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb b/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
index ae567882899..cec3563ddc5 100644
--- a/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/pushbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/pushbutton.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/radiobox.rb b/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
index 21181777b52..1c9e9f8d346 100644
--- a/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/radiobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/radiobox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb b/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
index 056cd853220..e17fee98dc4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scopedobject.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/buttonbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
index 4dea2f2d5c6..463689f5139 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledcanvas.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledcanvas.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
index 7b7b95df1cd..f105576fd68 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
index dc2966bd486..4ee5abe9fc4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledhtml.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledhtml.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
index 20a4cd1d362..94949c5524d 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledlistbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledlistbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
index 69b7d314fd1..1e2898988c9 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledtext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledtext.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb b/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
index 5ecd2d72d22..a8b4e5a27bc 100644
--- a/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/scrolledwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/scrolledwidget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb b/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
index eb8fe3ad522..333f68e306b 100644
--- a/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/selectionbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/selectionbox.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb b/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
index 45aecf32668..0d0b94e8d25 100644
--- a/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/selectiondialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/selectiondialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/setup.rb b/ext/tk/lib/tkextlib/iwidgets/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/iwidgets/setup.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/iwidgets/shell.rb b/ext/tk/lib/tkextlib/iwidgets/shell.rb
index c560e3ac29a..f09e7d4d318 100644
--- a/ext/tk/lib/tkextlib/iwidgets/shell.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/shell.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/shell.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spindate.rb b/ext/tk/lib/tkextlib/iwidgets/spindate.rb
index b3de9ed9899..8860348cc02 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spindate.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spindate.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/spindate.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spinint.rb b/ext/tk/lib/tkextlib/iwidgets/spinint.rb
index bede3bb1bfa..85736d095cb 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spinint.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spinint.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/spinint.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spinner.rb b/ext/tk/lib/tkextlib/iwidgets/spinner.rb
index d960996e22e..49968e86d89 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spinner.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spinner.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/spinner.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/spintime.rb b/ext/tk/lib/tkextlib/iwidgets/spintime.rb
index 20f8197a099..9b280ec0e43 100644
--- a/ext/tk/lib/tkextlib/iwidgets/spintime.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/spintime.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/spintime.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb b/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
index f56efa9aaf3..89e33621856 100644
--- a/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/tabnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/tabnotebook.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/tabset.rb b/ext/tk/lib/tkextlib/iwidgets/tabset.rb
index 501ead49640..816ea087efa 100644
--- a/ext/tk/lib/tkextlib/iwidgets/tabset.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/tabset.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/tabset.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/timeentry.rb b/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
index b0afb3afd94..d4078e6e4f2 100644
--- a/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/timeentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/timeentry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/timefield.rb b/ext/tk/lib/tkextlib/iwidgets/timefield.rb
index c34281d4ff8..d759a0762f4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/timefield.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/timefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/timefield.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/toolbar.rb b/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
index 5b474c3816f..7f2a54b88b4 100644
--- a/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/toolbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/toolbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/iwidgets/watch.rb b/ext/tk/lib/tkextlib/iwidgets/watch.rb
index f10ec54cb29..c6e862b36a6 100644
--- a/ext/tk/lib/tkextlib/iwidgets/watch.rb
+++ b/ext/tk/lib/tkextlib/iwidgets/watch.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/iwidgets/watch.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/pkg_checker.rb b/ext/tk/lib/tkextlib/pkg_checker.rb
index e2fd97bb6ae..76a25ca629b 100755
--- a/ext/tk/lib/tkextlib/pkg_checker.rb
+++ b/ext/tk/lib/tkextlib/pkg_checker.rb
@@ -1,4 +1,5 @@
#!/usr/bin/env ruby
+# frozen_string_literal: false
#
# Ruby/Tk extension library checker
#
diff --git a/ext/tk/lib/tkextlib/setup.rb b/ext/tk/lib/tkextlib/setup.rb
index 79facc5ee3f..08ad32e99bb 100644
--- a/ext/tk/lib/tkextlib/setup.rb
+++ b/ext/tk/lib/tkextlib/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before using Tk extension libraries
#
diff --git a/ext/tk/lib/tkextlib/tcllib.rb b/ext/tk/lib/tkextlib/tcllib.rb
index 28319897590..75d250cba49 100644
--- a/ext/tk/lib/tkextlib/tcllib.rb
+++ b/ext/tk/lib/tkextlib/tcllib.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tcllib extension support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/autoscroll.rb b/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
index 2def59bf734..ae45b84787a 100644
--- a/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
+++ b/ext/tk/lib/tkextlib/tcllib/autoscroll.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/autoscroll.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/calendar.rb b/ext/tk/lib/tkextlib/tcllib/calendar.rb
index b6843df1761..fa53603d915 100644
--- a/ext/tk/lib/tkextlib/tcllib/calendar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/calendar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/calendar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb b/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
index ba87cd3aae2..f3d1847d733 100644
--- a/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
+++ b/ext/tk/lib/tkextlib/tcllib/canvas_sqmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/canvas.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb b/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
index f4ffb48ece7..bb8b04a18b5 100644
--- a/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
+++ b/ext/tk/lib/tkextlib/tcllib/canvas_zoom.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/canvas.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/chatwidget.rb b/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
index ddb0340c316..34a8ca5094d 100644
--- a/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
+++ b/ext/tk/lib/tkextlib/tcllib/chatwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/chatwidget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/crosshair.rb b/ext/tk/lib/tkextlib/tcllib/crosshair.rb
index 49b5361e4fd..74cc0a881c8 100644
--- a/ext/tk/lib/tkextlib/tcllib/crosshair.rb
+++ b/ext/tk/lib/tkextlib/tcllib/crosshair.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/crosshair.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ctext.rb b/ext/tk/lib/tkextlib/tcllib/ctext.rb
index 308847c2336..1c61ec81a67 100644
--- a/ext/tk/lib/tkextlib/tcllib/ctext.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ctext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/ctext.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/cursor.rb b/ext/tk/lib/tkextlib/tcllib/cursor.rb
index 5c47f9709b0..4c93cfc0636 100644
--- a/ext/tk/lib/tkextlib/tcllib/cursor.rb
+++ b/ext/tk/lib/tkextlib/tcllib/cursor.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/cursor.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/dateentry.rb b/ext/tk/lib/tkextlib/tcllib/dateentry.rb
index 77038d95bc4..81b38515fcb 100644
--- a/ext/tk/lib/tkextlib/tcllib/dateentry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/dateentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/dateentry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/datefield.rb b/ext/tk/lib/tkextlib/tcllib/datefield.rb
index 4c2eae741eb..ceed1260dfa 100644
--- a/ext/tk/lib/tkextlib/tcllib/datefield.rb
+++ b/ext/tk/lib/tkextlib/tcllib/datefield.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/datefield.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/diagrams.rb b/ext/tk/lib/tkextlib/tcllib/diagrams.rb
index d24ba9d2321..7fb7b3c7ee1 100644
--- a/ext/tk/lib/tkextlib/tcllib/diagrams.rb
+++ b/ext/tk/lib/tkextlib/tcllib/diagrams.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/diagrams.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/dialog.rb b/ext/tk/lib/tkextlib/tcllib/dialog.rb
index 86a0ef22698..46fd06f1770 100644
--- a/ext/tk/lib/tkextlib/tcllib/dialog.rb
+++ b/ext/tk/lib/tkextlib/tcllib/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/dialog.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/getstring.rb b/ext/tk/lib/tkextlib/tcllib/getstring.rb
index 48711d3b66f..72d9c5f5175 100644
--- a/ext/tk/lib/tkextlib/tcllib/getstring.rb
+++ b/ext/tk/lib/tkextlib/tcllib/getstring.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/getstring.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/history.rb b/ext/tk/lib/tkextlib/tcllib/history.rb
index a01a4ebfcce..a1b92726eea 100644
--- a/ext/tk/lib/tkextlib/tcllib/history.rb
+++ b/ext/tk/lib/tkextlib/tcllib/history.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/history.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ico.rb b/ext/tk/lib/tkextlib/tcllib/ico.rb
index 36a32c6b09e..8814205f94a 100644
--- a/ext/tk/lib/tkextlib/tcllib/ico.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/ico.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ip_entry.rb b/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
index 4878cc3c230..6bbd8442a6b 100644
--- a/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ip_entry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/ip_entry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/khim.rb b/ext/tk/lib/tkextlib/tcllib/khim.rb
index 5dc2130b35a..e79f26b3815 100644
--- a/ext/tk/lib/tkextlib/tcllib/khim.rb
+++ b/ext/tk/lib/tkextlib/tcllib/khim.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/khim.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/menuentry.rb b/ext/tk/lib/tkextlib/tcllib/menuentry.rb
index f1eb2f295cf..51521499da7 100644
--- a/ext/tk/lib/tkextlib/tcllib/menuentry.rb
+++ b/ext/tk/lib/tkextlib/tcllib/menuentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/menuentry.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ntext.rb b/ext/tk/lib/tkextlib/tcllib/ntext.rb
index 7888ed48715..2d0c208236b 100644
--- a/ext/tk/lib/tkextlib/tcllib/ntext.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ntext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/ntext.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/panelframe.rb b/ext/tk/lib/tkextlib/tcllib/panelframe.rb
index 020c51cbd1f..678d5d0a9a7 100644
--- a/ext/tk/lib/tkextlib/tcllib/panelframe.rb
+++ b/ext/tk/lib/tkextlib/tcllib/panelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/panelframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/plotchart.rb b/ext/tk/lib/tkextlib/tcllib/plotchart.rb
index a1ebe86692f..1817f9a791a 100644
--- a/ext/tk/lib/tkextlib/tcllib/plotchart.rb
+++ b/ext/tk/lib/tkextlib/tcllib/plotchart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/plotchart.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/ruler.rb b/ext/tk/lib/tkextlib/tcllib/ruler.rb
index d22dafa053c..f57b0b0e1a5 100644
--- a/ext/tk/lib/tkextlib/tcllib/ruler.rb
+++ b/ext/tk/lib/tkextlib/tcllib/ruler.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/ruler.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/screenruler.rb b/ext/tk/lib/tkextlib/tcllib/screenruler.rb
index 75fa36b66d8..64dd4f4ccc2 100644
--- a/ext/tk/lib/tkextlib/tcllib/screenruler.rb
+++ b/ext/tk/lib/tkextlib/tcllib/screenruler.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/screenruler.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb b/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
index c9488b46868..380d301a1aa 100644
--- a/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
+++ b/ext/tk/lib/tkextlib/tcllib/scrolledwindow.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/scrolledwindow.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/scrollwin.rb b/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
index c9f6062feff..f9bf127799e 100644
--- a/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
+++ b/ext/tk/lib/tkextlib/tcllib/scrollwin.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/scrollwin.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/setup.rb b/ext/tk/lib/tkextlib/tcllib/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tcllib/setup.rb
+++ b/ext/tk/lib/tkextlib/tcllib/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tcllib/statusbar.rb b/ext/tk/lib/tkextlib/tcllib/statusbar.rb
index 46a4b9d8b67..b2c8f54b94b 100644
--- a/ext/tk/lib/tkextlib/tcllib/statusbar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/statusbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/statusbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/style.rb b/ext/tk/lib/tkextlib/tcllib/style.rb
index dac6916e468..f3b66b7861d 100644
--- a/ext/tk/lib/tkextlib/tcllib/style.rb
+++ b/ext/tk/lib/tkextlib/tcllib/style.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/style.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/superframe.rb b/ext/tk/lib/tkextlib/tcllib/superframe.rb
index adc9c4adbd5..776ad7c166f 100644
--- a/ext/tk/lib/tkextlib/tcllib/superframe.rb
+++ b/ext/tk/lib/tkextlib/tcllib/superframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/superframe.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/swaplist.rb b/ext/tk/lib/tkextlib/tcllib/swaplist.rb
index 76986405349..7eaed8dbaa2 100644
--- a/ext/tk/lib/tkextlib/tcllib/swaplist.rb
+++ b/ext/tk/lib/tkextlib/tcllib/swaplist.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/swaplist.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist.rb b/ext/tk/lib/tkextlib/tcllib/tablelist.rb
index bf5ab6620aa..7cfe2faf1e5 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/tablelist.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb b/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
index 2a5c415cc7a..b45f18796a4 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist_core.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/tablelist_core.rb
#
diff --git a/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb b/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
index 0a1458415ef..20488fdd485 100644
--- a/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tablelist_tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/tablelist_tlie.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb b/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
index 2f6e4b44fc6..2fc75a68ec9 100644
--- a/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tkpiechart.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/tkpiechart.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/toolbar.rb b/ext/tk/lib/tkextlib/tcllib/toolbar.rb
index 6eae4eb3e18..ae05a16e05f 100644
--- a/ext/tk/lib/tkextlib/tcllib/toolbar.rb
+++ b/ext/tk/lib/tkextlib/tcllib/toolbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/toolbar.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/tooltip.rb b/ext/tk/lib/tkextlib/tcllib/tooltip.rb
index 070e63a7b53..4a70ec5732b 100644
--- a/ext/tk/lib/tkextlib/tcllib/tooltip.rb
+++ b/ext/tk/lib/tkextlib/tcllib/tooltip.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/tooltip.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/validator.rb b/ext/tk/lib/tkextlib/tcllib/validator.rb
index 3a71960afa6..c2c9dda3762 100644
--- a/ext/tk/lib/tkextlib/tcllib/validator.rb
+++ b/ext/tk/lib/tkextlib/tcllib/validator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/validator.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tcllib/widget.rb b/ext/tk/lib/tkextlib/tcllib/widget.rb
index 57fdf7a575b..b8d5070b0b0 100644
--- a/ext/tk/lib/tkextlib/tcllib/widget.rb
+++ b/ext/tk/lib/tkextlib/tcllib/widget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tcllib/widget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tclx.rb b/ext/tk/lib/tkextlib/tclx.rb
index 3a4ff276446..1189d855cb7 100644
--- a/ext/tk/lib/tkextlib/tclx.rb
+++ b/ext/tk/lib/tkextlib/tclx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TclX support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tclx/setup.rb b/ext/tk/lib/tkextlib/tclx/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tclx/setup.rb
+++ b/ext/tk/lib/tkextlib/tclx/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tclx/tclx.rb b/ext/tk/lib/tkextlib/tclx/tclx.rb
index 5a908fcd0b2..7360a854035 100644
--- a/ext/tk/lib/tkextlib/tclx/tclx.rb
+++ b/ext/tk/lib/tkextlib/tclx/tclx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tclx/tclx.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile.rb b/ext/tk/lib/tkextlib/tile.rb
index 6c11e212ae1..ef153510662 100644
--- a/ext/tk/lib/tkextlib/tile.rb
+++ b/ext/tk/lib/tkextlib/tile.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# Tile theme engin (tile widget set) support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/dialog.rb b/ext/tk/lib/tkextlib/tile/dialog.rb
index b112e6152bc..d81851bb685 100644
--- a/ext/tk/lib/tkextlib/tile/dialog.rb
+++ b/ext/tk/lib/tkextlib/tile/dialog.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ttk::dialog (tile-0.7+)
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/setup.rb b/ext/tk/lib/tkextlib/tile/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tile/setup.rb
+++ b/ext/tk/lib/tkextlib/tile/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tile/sizegrip.rb b/ext/tk/lib/tkextlib/tile/sizegrip.rb
index 9947e0d870b..4b9510aefa1 100644
--- a/ext/tk/lib/tkextlib/tile/sizegrip.rb
+++ b/ext/tk/lib/tkextlib/tile/sizegrip.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ttk::sizegrip widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/style.rb b/ext/tk/lib/tkextlib/tile/style.rb
index 83a0c9a2e8b..a96cba795f4 100644
--- a/ext/tk/lib/tkextlib/tile/style.rb
+++ b/ext/tk/lib/tkextlib/tile/style.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# style commands
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tbutton.rb b/ext/tk/lib/tkextlib/tile/tbutton.rb
index c852024842a..217da62eca8 100644
--- a/ext/tk/lib/tkextlib/tile/tbutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tbutton widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tcheckbutton.rb b/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
index 01751ede0f3..c0e4d4b5057 100644
--- a/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tcheckbutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tcheckbutton widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tcombobox.rb b/ext/tk/lib/tkextlib/tile/tcombobox.rb
index b5ab827e2da..f2dec21fbf4 100644
--- a/ext/tk/lib/tkextlib/tile/tcombobox.rb
+++ b/ext/tk/lib/tkextlib/tile/tcombobox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tcombobox widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tentry.rb b/ext/tk/lib/tkextlib/tile/tentry.rb
index 8d2633a7746..5d577a65a6d 100644
--- a/ext/tk/lib/tkextlib/tile/tentry.rb
+++ b/ext/tk/lib/tkextlib/tile/tentry.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tentry widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tframe.rb b/ext/tk/lib/tkextlib/tile/tframe.rb
index d6d43126288..5ebf19d1e8a 100644
--- a/ext/tk/lib/tkextlib/tile/tframe.rb
+++ b/ext/tk/lib/tkextlib/tile/tframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tframe widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tlabel.rb b/ext/tk/lib/tkextlib/tile/tlabel.rb
index 55b98acc681..3dddeafc218 100644
--- a/ext/tk/lib/tkextlib/tile/tlabel.rb
+++ b/ext/tk/lib/tkextlib/tile/tlabel.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tlabel widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tlabelframe.rb b/ext/tk/lib/tkextlib/tile/tlabelframe.rb
index a34c98583f5..d512f31ffe6 100644
--- a/ext/tk/lib/tkextlib/tile/tlabelframe.rb
+++ b/ext/tk/lib/tkextlib/tile/tlabelframe.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tlabelframe widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tmenubutton.rb b/ext/tk/lib/tkextlib/tile/tmenubutton.rb
index 1cf553ec8c1..a22ebaeca79 100644
--- a/ext/tk/lib/tkextlib/tile/tmenubutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tmenubutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tmenubutton widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tnotebook.rb b/ext/tk/lib/tkextlib/tile/tnotebook.rb
index 9e27e2c1fd5..4089dcfd4ba 100644
--- a/ext/tk/lib/tkextlib/tile/tnotebook.rb
+++ b/ext/tk/lib/tkextlib/tile/tnotebook.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tnotebook widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tpaned.rb b/ext/tk/lib/tkextlib/tile/tpaned.rb
index d6ad2345590..f51a1f3b419 100644
--- a/ext/tk/lib/tkextlib/tile/tpaned.rb
+++ b/ext/tk/lib/tkextlib/tile/tpaned.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tpaned widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tprogressbar.rb b/ext/tk/lib/tkextlib/tile/tprogressbar.rb
index 0c9d15e1b9c..446e053e3bd 100644
--- a/ext/tk/lib/tkextlib/tile/tprogressbar.rb
+++ b/ext/tk/lib/tkextlib/tile/tprogressbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tprogressbar widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tradiobutton.rb b/ext/tk/lib/tkextlib/tile/tradiobutton.rb
index 5dbf2606665..202de1eb25b 100644
--- a/ext/tk/lib/tkextlib/tile/tradiobutton.rb
+++ b/ext/tk/lib/tkextlib/tile/tradiobutton.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tradiobutton widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/treeview.rb b/ext/tk/lib/tkextlib/tile/treeview.rb
index 85d7831671b..1be8f543488 100644
--- a/ext/tk/lib/tkextlib/tile/treeview.rb
+++ b/ext/tk/lib/tkextlib/tile/treeview.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# treeview widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tscale.rb b/ext/tk/lib/tkextlib/tile/tscale.rb
index 7eefcef7317..446344ecea7 100644
--- a/ext/tk/lib/tkextlib/tile/tscale.rb
+++ b/ext/tk/lib/tkextlib/tile/tscale.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tscale & tprogress widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tscrollbar.rb b/ext/tk/lib/tkextlib/tile/tscrollbar.rb
index c6bba5810bb..621ca48efb9 100644
--- a/ext/tk/lib/tkextlib/tile/tscrollbar.rb
+++ b/ext/tk/lib/tkextlib/tile/tscrollbar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tscrollbar widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tseparator.rb b/ext/tk/lib/tkextlib/tile/tseparator.rb
index ffd2f6f89f0..d4a90e56dbf 100644
--- a/ext/tk/lib/tkextlib/tile/tseparator.rb
+++ b/ext/tk/lib/tkextlib/tile/tseparator.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tseparator widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tspinbox.rb b/ext/tk/lib/tkextlib/tile/tspinbox.rb
index 2f2d73c5ab8..47d822e68ce 100644
--- a/ext/tk/lib/tkextlib/tile/tspinbox.rb
+++ b/ext/tk/lib/tkextlib/tile/tspinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ttk::spinbox widget (Tcl/Tk 8.6b1 or later)
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tile/tsquare.rb b/ext/tk/lib/tkextlib/tile/tsquare.rb
index a81cd7b98a8..74129667089 100644
--- a/ext/tk/lib/tkextlib/tile/tsquare.rb
+++ b/ext/tk/lib/tkextlib/tile/tsquare.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tsquare widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND.rb b/ext/tk/lib/tkextlib/tkDND.rb
index 5d52e344186..c76c48d1690 100644
--- a/ext/tk/lib/tkextlib/tkDND.rb
+++ b/ext/tk/lib/tkextlib/tkDND.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkDND (Tk Drag & Drop Extension) support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND/setup.rb b/ext/tk/lib/tkextlib/tkDND/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tkDND/setup.rb
+++ b/ext/tk/lib/tkextlib/tkDND/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tkDND/shape.rb b/ext/tk/lib/tkextlib/tkDND/shape.rb
index d44068ed338..06d8d64ac7b 100644
--- a/ext/tk/lib/tkextlib/tkDND/shape.rb
+++ b/ext/tk/lib/tkextlib/tkDND/shape.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tkDND/shape.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkDND/tkdnd.rb b/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
index 38e05ce7757..c2059b7c237 100644
--- a/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
+++ b/ext/tk/lib/tkextlib/tkDND/tkdnd.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tkDND/tkdnd.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML.rb b/ext/tk/lib/tkextlib/tkHTML.rb
index 5fddde72ff8..d64e6760241 100644
--- a/ext/tk/lib/tkextlib/tkHTML.rb
+++ b/ext/tk/lib/tkextlib/tkHTML.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkHtml support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb b/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
index b9ee90aace4..362c3818304 100644
--- a/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
+++ b/ext/tk/lib/tkextlib/tkHTML/htmlwidget.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tkHTML/htmlwidget.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkHTML/setup.rb b/ext/tk/lib/tkextlib/tkHTML/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tkHTML/setup.rb
+++ b/ext/tk/lib/tkextlib/tkHTML/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tkimg.rb b/ext/tk/lib/tkextlib/tkimg.rb
index c01359d3efb..de4b7212c3c 100644
--- a/ext/tk/lib/tkextlib/tkimg.rb
+++ b/ext/tk/lib/tkextlib/tkimg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg extension support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/bmp.rb b/ext/tk/lib/tkextlib/tkimg/bmp.rb
index ea90181aa38..48a3b7ef5fc 100644
--- a/ext/tk/lib/tkextlib/tkimg/bmp.rb
+++ b/ext/tk/lib/tkextlib/tkimg/bmp.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'bmp'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/dted.rb b/ext/tk/lib/tkextlib/tkimg/dted.rb
index cae833664ce..30c595c1b60 100644
--- a/ext/tk/lib/tkextlib/tkimg/dted.rb
+++ b/ext/tk/lib/tkextlib/tkimg/dted.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'DTED'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/gif.rb b/ext/tk/lib/tkextlib/tkimg/gif.rb
index d542d475611..ce5f3e94ec6 100644
--- a/ext/tk/lib/tkextlib/tkimg/gif.rb
+++ b/ext/tk/lib/tkextlib/tkimg/gif.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'gif'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ico.rb b/ext/tk/lib/tkextlib/tkimg/ico.rb
index e79bdf45e9c..80656005f0c 100644
--- a/ext/tk/lib/tkextlib/tkimg/ico.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'ico'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/jpeg.rb b/ext/tk/lib/tkextlib/tkimg/jpeg.rb
index 21261201619..24e11a84ded 100644
--- a/ext/tk/lib/tkextlib/tkimg/jpeg.rb
+++ b/ext/tk/lib/tkextlib/tkimg/jpeg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'jpeg'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/pcx.rb b/ext/tk/lib/tkextlib/tkimg/pcx.rb
index 6831f4d35bd..942d585120f 100644
--- a/ext/tk/lib/tkextlib/tkimg/pcx.rb
+++ b/ext/tk/lib/tkextlib/tkimg/pcx.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'pcx'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)#
diff --git a/ext/tk/lib/tkextlib/tkimg/pixmap.rb b/ext/tk/lib/tkextlib/tkimg/pixmap.rb
index bd1b870af79..b90468a108c 100644
--- a/ext/tk/lib/tkextlib/tkimg/pixmap.rb
+++ b/ext/tk/lib/tkextlib/tkimg/pixmap.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'pixmap'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/png.rb b/ext/tk/lib/tkextlib/tkimg/png.rb
index 5c829f48d28..76f73297722 100644
--- a/ext/tk/lib/tkextlib/tkimg/png.rb
+++ b/ext/tk/lib/tkextlib/tkimg/png.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'png'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ppm.rb b/ext/tk/lib/tkextlib/tkimg/ppm.rb
index eacfae467df..a6b705e6add 100644
--- a/ext/tk/lib/tkextlib/tkimg/ppm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ppm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'ppm'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/ps.rb b/ext/tk/lib/tkextlib/tkimg/ps.rb
index 68e9178ac0d..2a450ed1579 100644
--- a/ext/tk/lib/tkextlib/tkimg/ps.rb
+++ b/ext/tk/lib/tkextlib/tkimg/ps.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'ps'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/raw.rb b/ext/tk/lib/tkextlib/tkimg/raw.rb
index 5f1cdcaac03..2eddbbc43a2 100644
--- a/ext/tk/lib/tkextlib/tkimg/raw.rb
+++ b/ext/tk/lib/tkextlib/tkimg/raw.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'Raw Data'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/setup.rb b/ext/tk/lib/tkextlib/tkimg/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tkimg/setup.rb
+++ b/ext/tk/lib/tkextlib/tkimg/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tkimg/sgi.rb b/ext/tk/lib/tkextlib/tkimg/sgi.rb
index ec7038bf0ef..73a5bce0ac9 100644
--- a/ext/tk/lib/tkextlib/tkimg/sgi.rb
+++ b/ext/tk/lib/tkextlib/tkimg/sgi.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'sgi'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/sun.rb b/ext/tk/lib/tkextlib/tkimg/sun.rb
index 651f9464974..bd1ac0e5777 100644
--- a/ext/tk/lib/tkextlib/tkimg/sun.rb
+++ b/ext/tk/lib/tkextlib/tkimg/sun.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'sun'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/tga.rb b/ext/tk/lib/tkextlib/tkimg/tga.rb
index 1eae407c0ac..1dd499b9538 100644
--- a/ext/tk/lib/tkextlib/tkimg/tga.rb
+++ b/ext/tk/lib/tkextlib/tkimg/tga.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'tga'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/tiff.rb b/ext/tk/lib/tkextlib/tkimg/tiff.rb
index ed271c2600c..a2d1d8fcc55 100644
--- a/ext/tk/lib/tkextlib/tkimg/tiff.rb
+++ b/ext/tk/lib/tkextlib/tkimg/tiff.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'tiff'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/window.rb b/ext/tk/lib/tkextlib/tkimg/window.rb
index 3b5906fab6a..346f246aa4e 100644
--- a/ext/tk/lib/tkextlib/tkimg/window.rb
+++ b/ext/tk/lib/tkextlib/tkimg/window.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'window'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/xbm.rb b/ext/tk/lib/tkextlib/tkimg/xbm.rb
index f4bea030bed..0a4deffdd7a 100644
--- a/ext/tk/lib/tkextlib/tkimg/xbm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/xbm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'xbm'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tkimg/xpm.rb b/ext/tk/lib/tkextlib/tkimg/xpm.rb
index 5119c8710b1..7708b9d427a 100644
--- a/ext/tk/lib/tkextlib/tkimg/xpm.rb
+++ b/ext/tk/lib/tkextlib/tkimg/xpm.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkImg - format 'xpm'
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktable.rb b/ext/tk/lib/tkextlib/tktable.rb
index 385eb13497a..a957294db0f 100644
--- a/ext/tk/lib/tkextlib/tktable.rb
+++ b/ext/tk/lib/tkextlib/tktable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkTable support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktable/setup.rb b/ext/tk/lib/tkextlib/tktable/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tktable/setup.rb
+++ b/ext/tk/lib/tkextlib/tktable/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tktable/tktable.rb b/ext/tk/lib/tkextlib/tktable/tktable.rb
index f7074655eda..d8811a96763 100644
--- a/ext/tk/lib/tkextlib/tktable/tktable.rb
+++ b/ext/tk/lib/tkextlib/tktable/tktable.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/tktable/tktable.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktrans.rb b/ext/tk/lib/tkextlib/tktrans.rb
index c5de5be5e60..031eeb9fd72 100644
--- a/ext/tk/lib/tkextlib/tktrans.rb
+++ b/ext/tk/lib/tkextlib/tktrans.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkTrans support (win32 only)
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/tktrans/setup.rb b/ext/tk/lib/tkextlib/tktrans/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/tktrans/setup.rb
+++ b/ext/tk/lib/tkextlib/tktrans/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/tktrans/tktrans.rb b/ext/tk/lib/tkextlib/tktrans/tktrans.rb
index e051c092111..e6e0e3a78dc 100644
--- a/ext/tk/lib/tkextlib/tktrans/tktrans.rb
+++ b/ext/tk/lib/tkextlib/tktrans/tktrans.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkTrans support (win32 only)
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/treectrl.rb b/ext/tk/lib/tkextlib/treectrl.rb
index 1944fb83e3f..227d55ff1e0 100644
--- a/ext/tk/lib/tkextlib/treectrl.rb
+++ b/ext/tk/lib/tkextlib/treectrl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# TkTreeCtrl support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/treectrl/setup.rb b/ext/tk/lib/tkextlib/treectrl/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/treectrl/setup.rb
+++ b/ext/tk/lib/tkextlib/treectrl/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb b/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
index 1879a531ae5..dbd59f8c05c 100644
--- a/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
+++ b/ext/tk/lib/tkextlib/treectrl/tktreectrl.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/treectrl/tktreectrl.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/trofs.rb b/ext/tk/lib/tkextlib/trofs.rb
index 5914e5165fe..46581a3dad3 100644
--- a/ext/tk/lib/tkextlib/trofs.rb
+++ b/ext/tk/lib/tkextlib/trofs.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# trofs support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/trofs/setup.rb b/ext/tk/lib/tkextlib/trofs/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/trofs/setup.rb
+++ b/ext/tk/lib/tkextlib/trofs/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/trofs/trofs.rb b/ext/tk/lib/tkextlib/trofs/trofs.rb
index 7a2606a275d..dc55ec269a9 100644
--- a/ext/tk/lib/tkextlib/trofs/trofs.rb
+++ b/ext/tk/lib/tkextlib/trofs/trofs.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/trofs/trofs.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/version.rb b/ext/tk/lib/tkextlib/version.rb
index 4bef78fe545..68c8ae31a24 100644
--- a/ext/tk/lib/tkextlib/version.rb
+++ b/ext/tk/lib/tkextlib/version.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# release date of tkextlib
#
diff --git a/ext/tk/lib/tkextlib/vu.rb b/ext/tk/lib/tkextlib/vu.rb
index d2234eb2a86..145a0b56478 100644
--- a/ext/tk/lib/tkextlib/vu.rb
+++ b/ext/tk/lib/tkextlib/vu.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# The vu widget set support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/bargraph.rb b/ext/tk/lib/tkextlib/vu/bargraph.rb
index b9fcf925f39..e1d58e9555a 100644
--- a/ext/tk/lib/tkextlib/vu/bargraph.rb
+++ b/ext/tk/lib/tkextlib/vu/bargraph.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ::vu::bargraph widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/charts.rb b/ext/tk/lib/tkextlib/vu/charts.rb
index 8569ac55414..66d5cfd3943 100644
--- a/ext/tk/lib/tkextlib/vu/charts.rb
+++ b/ext/tk/lib/tkextlib/vu/charts.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# charts -- Create and manipulate canvas Add-On Items
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/dial.rb b/ext/tk/lib/tkextlib/vu/dial.rb
index 4d04974a55d..7eb5650df07 100644
--- a/ext/tk/lib/tkextlib/vu/dial.rb
+++ b/ext/tk/lib/tkextlib/vu/dial.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ::vu::dial widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/pie.rb b/ext/tk/lib/tkextlib/vu/pie.rb
index 6b0c485d8ae..fb9920cc68e 100644
--- a/ext/tk/lib/tkextlib/vu/pie.rb
+++ b/ext/tk/lib/tkextlib/vu/pie.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ::vu::pie widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/vu/setup.rb b/ext/tk/lib/tkextlib/vu/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/vu/setup.rb
+++ b/ext/tk/lib/tkextlib/vu/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/vu/spinbox.rb b/ext/tk/lib/tkextlib/vu/spinbox.rb
index 7d6104f4d1c..082ebd1f62a 100644
--- a/ext/tk/lib/tkextlib/vu/spinbox.rb
+++ b/ext/tk/lib/tkextlib/vu/spinbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# ::vu::spinbox widget
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/winico.rb b/ext/tk/lib/tkextlib/winico.rb
index ce7b8eac5c0..996fc409b8f 100644
--- a/ext/tk/lib/tkextlib/winico.rb
+++ b/ext/tk/lib/tkextlib/winico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# winico -- Windows Icon extension support
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkextlib/winico/setup.rb b/ext/tk/lib/tkextlib/winico/setup.rb
index ee406c6ca05..cc967dced63 100644
--- a/ext/tk/lib/tkextlib/winico/setup.rb
+++ b/ext/tk/lib/tkextlib/winico/setup.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# setup.rb -- setup script before calling TkPackage.require()
#
diff --git a/ext/tk/lib/tkextlib/winico/winico.rb b/ext/tk/lib/tkextlib/winico/winico.rb
index 9160c2960fd..dda0357a164 100644
--- a/ext/tk/lib/tkextlib/winico/winico.rb
+++ b/ext/tk/lib/tkextlib/winico/winico.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkextlib/winico/winico.rb
# by Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)
diff --git a/ext/tk/lib/tkfont.rb b/ext/tk/lib/tkfont.rb
index 38a96633de1..6036006aac0 100644
--- a/ext/tk/lib/tkfont.rb
+++ b/ext/tk/lib/tkfont.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkfont.rb - load tk/font.rb
#
diff --git a/ext/tk/lib/tkmacpkg.rb b/ext/tk/lib/tkmacpkg.rb
index 35560e78ce3..4f76c2feb8b 100644
--- a/ext/tk/lib/tkmacpkg.rb
+++ b/ext/tk/lib/tkmacpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkmacpkg.rb - load tk/macpkg.rb
#
diff --git a/ext/tk/lib/tkmenubar.rb b/ext/tk/lib/tkmenubar.rb
index 70214fda1aa..43109e2b673 100644
--- a/ext/tk/lib/tkmenubar.rb
+++ b/ext/tk/lib/tkmenubar.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkmenubar.rb - load tk/menubar.rb
#
diff --git a/ext/tk/lib/tkmngfocus.rb b/ext/tk/lib/tkmngfocus.rb
index fe70950e8e8..43abd210c9b 100644
--- a/ext/tk/lib/tkmngfocus.rb
+++ b/ext/tk/lib/tkmngfocus.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkmngfocus.rb - load tk/mngfocus.rb
#
diff --git a/ext/tk/lib/tkpalette.rb b/ext/tk/lib/tkpalette.rb
index 56b203bbb96..f4e7321c47c 100644
--- a/ext/tk/lib/tkpalette.rb
+++ b/ext/tk/lib/tkpalette.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkpalette.rb - load tk/palette.rb
#
diff --git a/ext/tk/lib/tkscrollbox.rb b/ext/tk/lib/tkscrollbox.rb
index 6093b2e4e7d..c316ce2ea68 100644
--- a/ext/tk/lib/tkscrollbox.rb
+++ b/ext/tk/lib/tkscrollbox.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkscrollbox.rb - load tk/scrollbox.rb
#
diff --git a/ext/tk/lib/tktext.rb b/ext/tk/lib/tktext.rb
index 97ad62a3ea0..8ed41ac15ad 100644
--- a/ext/tk/lib/tktext.rb
+++ b/ext/tk/lib/tktext.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tktext.rb - load tk/text.rb
#
diff --git a/ext/tk/lib/tkvirtevent.rb b/ext/tk/lib/tkvirtevent.rb
index f4fae19a0ac..4efa790505f 100644
--- a/ext/tk/lib/tkvirtevent.rb
+++ b/ext/tk/lib/tkvirtevent.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkvirtevent.rb - load tk/virtevent.rb
#
diff --git a/ext/tk/lib/tkwinpkg.rb b/ext/tk/lib/tkwinpkg.rb
index 83371c546df..97c84f8ab1d 100644
--- a/ext/tk/lib/tkwinpkg.rb
+++ b/ext/tk/lib/tkwinpkg.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
#
# tkwinpkg.rb - load tk/winpkg.rb
#