13 files changed, 13 insertions, 0 deletions
diff --git a/ext/tk/sample/tkextlib/blt/barchart5.rb b/ext/tk/sample/tkextlib/blt/barchart5.rb
index 86101b200d..f818ffc375 100644
--- a/ext/tk/sample/tkextlib/blt/barchart5.rb
+++ b/ext/tk/sample/tkextlib/blt/barchart5.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/calendar.rb b/ext/tk/sample/tkextlib/blt/calendar.rb
index 86d34043dc..daae5fdcba 100644
--- a/ext/tk/sample/tkextlib/blt/calendar.rb
+++ b/ext/tk/sample/tkextlib/blt/calendar.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 
 require 'tk'
 require 'tkextlib/blt'
diff --git a/ext/tk/sample/tkextlib/blt/graph6.rb b/ext/tk/sample/tkextlib/blt/graph6.rb
index b3eeb81231..26baa527ef 100644
--- a/ext/tk/sample/tkextlib/blt/graph6.rb
+++ b/ext/tk/sample/tkextlib/blt/graph6.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 
 require 'tk'
 require 'tkextlib/blt'
diff --git a/ext/tk/sample/tkextlib/blt/graph7.rb b/ext/tk/sample/tkextlib/blt/graph7.rb
index 8b31b28c91..0e68388596 100644
--- a/ext/tk/sample/tkextlib/blt/graph7.rb
+++ b/ext/tk/sample/tkextlib/blt/graph7.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/graph7a.rb b/ext/tk/sample/tkextlib/blt/graph7a.rb
index 8def766060..aa744f1f74 100644
--- a/ext/tk/sample/tkextlib/blt/graph7a.rb
+++ b/ext/tk/sample/tkextlib/blt/graph7a.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/graph7b.rb b/ext/tk/sample/tkextlib/blt/graph7b.rb
index 8b00f154b2..5b30c4bac0 100644
--- a/ext/tk/sample/tkextlib/blt/graph7b.rb
+++ b/ext/tk/sample/tkextlib/blt/graph7b.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/graph7c.rb b/ext/tk/sample/tkextlib/blt/graph7c.rb
index d4ed1a66ad..8cbf3223f1 100644
--- a/ext/tk/sample/tkextlib/blt/graph7c.rb
+++ b/ext/tk/sample/tkextlib/blt/graph7c.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/pareto.rb b/ext/tk/sample/tkextlib/blt/pareto.rb
index bf9a1ec749..987be45f06 100644
--- a/ext/tk/sample/tkextlib/blt/pareto.rb
+++ b/ext/tk/sample/tkextlib/blt/pareto.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 
 require 'tk'
 require 'tkextlib/blt'
diff --git a/ext/tk/sample/tkextlib/blt/plot1.rb b/ext/tk/sample/tkextlib/blt/plot1.rb
index 07dff48292..95797c96b7 100644
--- a/ext/tk/sample/tkextlib/blt/plot1.rb
+++ b/ext/tk/sample/tkextlib/blt/plot1.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/plot1b.rb b/ext/tk/sample/tkextlib/blt/plot1b.rb
index 8a3ce8216d..96adbd792b 100644
--- a/ext/tk/sample/tkextlib/blt/plot1b.rb
+++ b/ext/tk/sample/tkextlib/blt/plot1b.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/scripts/stipples.rb b/ext/tk/sample/tkextlib/blt/scripts/stipples.rb
index 47f3c4d063..2a4943e032 100644
--- a/ext/tk/sample/tkextlib/blt/scripts/stipples.rb
+++ b/ext/tk/sample/tkextlib/blt/scripts/stipples.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 $stipples = {} unless $stipples
 
 $stipples['bdiagonal1'] = Tk::BLT::Bitmap.new(<<EOD)
diff --git a/ext/tk/sample/tkextlib/blt/winop1.rb b/ext/tk/sample/tkextlib/blt/winop1.rb
index 97c31aa295..32c01cad6b 100644
--- a/ext/tk/sample/tkextlib/blt/winop1.rb
+++ b/ext/tk/sample/tkextlib/blt/winop1.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'
 
diff --git a/ext/tk/sample/tkextlib/blt/winop2.rb b/ext/tk/sample/tkextlib/blt/winop2.rb
index d59c43ba22..cc708573ab 100644
--- a/ext/tk/sample/tkextlib/blt/winop2.rb
+++ b/ext/tk/sample/tkextlib/blt/winop2.rb
@@ -1,4 +1,5 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: false
 require 'tk'
 require 'tkextlib/blt'