ronen / enumerable_hashify

enumerable_hashify

Defines Enumerable#hashify, which creates a hash with the enumerable's items as keys and with a given constant value or with block-computed values:

[1,2,3,4].hashify                --> {1=>true, 2=>true, 3=>true, 4=>true}
[1,2,3,4].hashify("a")           --> {1=>"a", 2=>"a", 3=>"a", 4=>"a"}
[1,2,3,4].hashify{|n| "a" * n}   --> {1=>"a", 2=>"aa", 3=>"aaa", 4=>"aaaa"}

Installation

gem install enumerable_hashify

or in your Gemfile

gem "enumerable_hashify"

Enumerable#hashify is now also available in the facets gem.

Tested on

MRI 1.8.7, MRI 1.9.3, MRI 2.0.0

Naming and Historical Note

I've been using this in my projects for years with the name Enumerable#to_h, and figured it was time to make a gem since nobody else seems to have.

But there's been a bunch of discussion online as to what the proper semantics that Enumerable#to_h should have, without universal agreement. I recently found a proposal from back in 2001 that suggested this same functionality with the name Enumerable#hashify which seemed pretty good to me. I don't know why that proposal wasn't adopted as part of ruby. But here it is as a gem.

Copyright

Released under the MIT License. See LICENSE for details.