From: nobu@...
Date: 2015-11-04T06:01:52+00:00
Subject: [ruby-core:71330] [Ruby trunk - Feature #11653] Add to_proc on Hash

Issue #11653 has been updated by Nobuyoshi Nakada.

Description updated

You can write it as:

~~~ruby
[:e, :a, :b, :f, :c, :d].map(&my_hash.method(:[]))
~~~

----------------------------------------
Feature #11653: Add to_proc on Hash
https://bugs.ruby-lang.org/issues/11653#change-54704

* Author: Daniel P. Clark
* Status: Open
* Priority: Normal
* Assignee: Yukihiro Matsumoto
----------------------------------------
Procs can be called the same way a hash is with `[]`.  But a Hash is not mappable as a Proc.

~~~ruby
    my_hash = ->key{{
      a: 1, b: 2, c: 3, d: 4, e: 5, f: 6
    }[key]}

    my_hash[:a]
    # => 1

    [:e, :a, :b, :f, :c, :d].map(&my_hash) # hash is now mappable
    # => [5, 1, 2, 6, 3, 4]
~~~

This seems so straight forward I believe it should be part of the language itself with the `.to_proc` method call.



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