Ruby | Proc | []

概要

Proc#self[*arg] -> ()
Proc#call(*arg) -> ()
Proc#self === *arg -> ()
Proc#yield(*arg) -> ()

詳細

手続きオブジェクトを実行してその結果を返却。
「 === 」 は case 文での利用のため。

サンプルコード

require 'tbpgr_utils'

pr = Proc.new { |msg| msg * 2 }

def use_case(msg, converted_message)
  case converted_message
  when msg.upcase then "upcase"
  when msg.downcase then "downcase"
  when Proc.new { |msg| msg * 2 } then "double"
  else
    "else"
  end
end

bulk_puts_eval binding, <<-EOS
pr["hoge"]
pr.call("hoge")
pr.("hoge")
pr === "hoge"
pr.yield("hoge")
use_case("hOgE", "HOGE")
use_case("hOgE", "hoge")
use_case("hOgE", "hOgEhOgE")
EOS


__END__
下記はTbpgrUtils gemの機能
bulk_puts_eval

https://rubygems.org/gems/tbpgr_utils
https://github.com/tbpgr/tbpgr_utils

出力

pr["hoge"]                   # => "hogehoge"
pr.call("hoge")              # => "hogehoge"
pr.("hoge")                  # => "hogehoge"
pr === "hoge"                # => "hogehoge"
pr.yield("hoge")             # => "hogehoge"
use_case("hOgE", "HOGE")     # => "upcase"
use_case("hOgE", "hoge")     # => "downcase"
use_case("hOgE", "hOgEhOgE") # => "double"

参照

http://docs.ruby-lang.org/ja/2.1.0/class/Proc.html#I_--3D--3D--3D