August 13th, 2007
Comprehensions in Ruby
Now, this is totally awesome. Jay found a way to implement generic comprehensions in Ruby. In twenty lines of code. It’s really quite obvious when you look at it. An example:
(1..100).find_all &it % 2 == 0
%w'sdfgsdfg foo bazar bara'.sort_by(&its.length).map &it.reverse.capitalize
%w'sdfgsdfg foo bazar bara'.map &:to_sym
%w'sdfgsdfg foo bazar bara'.map &it.to_sym
Now, the last two lines are what I like the most. The Symbol to_proc tric is widely used, but I actually think the comprehension version is more readable. It’s even better if replacing “map ” with “collect”.
This is actually real fun. You can link how many methods you like – you can send arguments to the methods, you can send blocks to them, you can link and nest however you want. It apples for Arrays, Sets, Hashes – everything you can send a block to can use this, so it’s not limited to collections or anything like that.
I think it’s really, really cool, and it should be part of Facets, ActiveSupport, hell, the Ruby core library. I want it there.
Now, the only, only, only quibble I have with it… He choose to call it “The Methodphitamine”. You should actually use ‘require “methodphitamine”‘. It’s a gem. I love it. But I hate the name. So, read more in his blog, here: http://jicksta.com/articles/2007/08/04/the-methodphitamine.
