From: Yukihiro Matsumoto <matz@...>
Date: 2011-11-03T19:40:22+09:00
Subject: [ruby-dev:44791] [ruby-trunk - Feature #5554][Feedback] A method that applies self to a Proc if self is a Symbol


Issue #5554 has been updated by Yukihiro Matsumoto.

Status changed from Open to Feedback

ごめんなさい。「本当に意図したのは」という部分の意図が読み取れません。
どのような局面でどのように嬉しいか(たとえば劇的にシンプルに記述できるから)を表現してください。
ただ単に「こんな風に書きたいと私が感じる」だとたぶん不十分です。
自分でメソッド定義するかActiveSupportに提案すれば良いわけで。
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Feature #5554: A method that applies self to a Proc if self is a Symbol
http://redmine.ruby-lang.org/issues/5554

Author: Tsuyoshi Sawada
Status: Feedback
Priority: Normal
Assignee: 
Category: 
Target version: 


Often, you want to apply a Proc to self if self is a Symbol, but not do anything if otherwise. In this case, something I call Object#desymbolize may be convenient:

    proc = ->sym{
        case sym
        when :small_icon  then "16pt"
        when :medium_icon then "32pt"
        when :large_icon  then "64pt"
        end
    }
    :small_icon.desymbolize(&proc) => "16pt"
    "18pt".desymbolize(&proc) => "18pt"

An implementation may be as follows:

class Object
	def desymbolize; self end
end
class Symbol
	def desymbolize &pr; pr.call(self) end
end



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