[ruby/optparse] Prefer Proc over Method

The performances are: block > proc > method object.

https://github.com/ruby/optparse/commit/9ec5d1d582

lib/optparse.rb

@@ -1855,7 +1855,7 @@ XXX
   #
   def permute!(argv = default_argv, **keywords)
     nonopts = []
-    order!(argv, **keywords, &nonopts.method(:<<))
+    order!(argv, **keywords) {|nonopt| nonopts << nonopt}
     argv[0, 0] = nonopts
     argv
   end
@@ -1908,13 +1908,16 @@ XXX
     single_options, *long_options = *args
 
     result = {}
+    setter = (symbolize_names ?
+                ->(name, val) {result[name.to_sym] = val}
+              : ->(name, val) {result[name] = val})
 
     single_options.scan(/(.)(:)?/) do |opt, val|
       if val
-        result[opt] = nil
+        setter[opt, nil]
         define("-#{opt} VAL")
       else
-        result[opt] = false
+        setter[opt, false]
         define("-#{opt}")
       end
     end if single_options
@@ -1923,16 +1926,16 @@ XXX
       arg, desc = arg.split(';', 2)
       opt, val = arg.split(':', 2)
       if val
-        result[opt] = val.empty? ? nil : val
+        setter[opt, (val unless val.empty?)]
         define("--#{opt}=#{result[opt] || "VAL"}", *[desc].compact)
       else
-        result[opt] = false
+        setter[opt, false]
         define("--#{opt}", *[desc].compact)
       end
     end
 
-    parse_in_order(argv, result.method(:[]=), **keywords)
-    symbolize_names ? result.transform_keys(&:to_sym) : result
+    parse_in_order(argv, setter, **keywords)
+    result
   end
 
   #
@@ -1982,7 +1985,7 @@ XXX
       visit(:complete, typ, opt, icase, *pat) {|o, *sw| return sw}
     }
     exc = ambiguous ? AmbiguousOption : InvalidOption
-    raise exc.new(opt, additional: self.method(:additional_message).curry[typ])
+    raise exc.new(opt, additional: proc {|o| additional_message(typ, o)})
   end
   private :complete
 
@@ -2273,9 +2276,10 @@ XXX
       argv
     end
 
+    DIR = File.join(__dir__, '')
     def self.filter_backtrace(array)
       unless $DEBUG
-        array.delete_if(&%r"\A#{Regexp.quote(__FILE__)}:"o.method(:=~))
+        array.delete_if {|bt| bt.start_with?(DIR)}
       end
       array
     end