From: Florian Gross <flgr@...>
Date: 2004-04-24T14:49:09+09:00
Subject: Re: Array to Hash

Ara.T.Howard wrote:

> On Sat, 24 Apr 2004 nobu.nokada@softhome.net wrote:
>>module Enumerable
>>  def to_h
>>    inject({}) {|h, (k, v)| h[k] = v; h}
> 
>                       ^^^^^^
>                       ^^^^^^
>                       ^^^^^^
>                       what's this?
> 

inject will get yielded the current state of the result Hash and a new 
[key, value] Array. The () syntax lets you access the components of that 
Array directly through the variables you use.

This is similar to this assignment:

pair, (key, value) = ["one", 1], ["two", 2]
pair  # => ["one", 1]
key   # => "two"
value # => 2

This is also explained in the Pickaxe book: 
http://www.rubycentral.com/book/tut_expressions.html#UD

Regards,
Florian Gross