1 files changed, 22 insertions, 3 deletions
diff --git a/lib/optparse/ac.rb b/lib/optparse/ac.rb
index fb0883f97a..23fc740d10 100644
--- a/lib/optparse/ac.rb
+++ b/lib/optparse/ac.rb
@@ -1,7 +1,11 @@
 # frozen_string_literal: false
-require 'optparse'
+require_relative '../optparse'
 
+#
+# autoconf-like options.
+#
 class OptionParser::AC < OptionParser
+  # :stopdoc:
   private
 
   def _check_ac_args(name, block)
@@ -13,6 +17,9 @@ class OptionParser::AC < OptionParser
     end
   end
 
+  ARG_CONV = proc {|val| val.nil? ? true : val}
+  private_constant :ARG_CONV
+
   def _ac_arg_enable(prefix, name, help_string, block)
     _check_ac_args(name, block)
 
@@ -20,22 +27,34 @@ class OptionParser::AC < OptionParser
     ldesc = ["--#{prefix}-#{name}"]
     desc = [help_string]
     q = name.downcase
-    enable = Switch::NoArgument.new(nil, proc {true}, sdesc, ldesc, nil, desc, block)
-    disable = Switch::NoArgument.new(nil, proc {false}, sdesc, ldesc, nil, desc, block)
+    ac_block = proc {|val| block.call(ARG_CONV.call(val))}
+    enable = Switch::PlacedArgument.new(nil, ARG_CONV, sdesc, ldesc, nil, desc, ac_block)
+    disable = Switch::NoArgument.new(nil, proc {false}, sdesc, ldesc, nil, desc, ac_block)
     top.append(enable, [], ["enable-" + q], disable, ['disable-' + q])
     enable
   end
 
+  # :startdoc:
+
   public
 
+  # Define <tt>--enable</tt> / <tt>--disable</tt> style option
+  #
+  # Appears as <tt>--enable-<i>name</i></tt> in help message.
   def ac_arg_enable(name, help_string, &block)
     _ac_arg_enable("enable", name, help_string, block)
   end
 
+  # Define <tt>--enable</tt> / <tt>--disable</tt> style option
+  #
+  # Appears as <tt>--disable-<i>name</i></tt> in help message.
   def ac_arg_disable(name, help_string, &block)
     _ac_arg_enable("disable", name, help_string, block)
   end
 
+  # Define <tt>--with</tt> / <tt>--without</tt> style option
+  #
+  # Appears as <tt>--with-<i>name</i></tt> in help message.
   def ac_arg_with(name, help_string, &block)
     _check_ac_args(name, block)