From: "David A. Black" <dblack@...>
Date: 2009-07-05T21:33:26+09:00
Subject: Re: to_proc and Proc/block conversion with &

Hi --

On Sun, 5 Jul 2009, Robert Dober wrote:

> On 7/5/09, David A. Black <dblack@rubypal.com> wrote:
>> Yes; the & means: take what's to the right of it (which can be any
>> expression), evaluate it, call to_proc on the resulting object, and
>> use the return value of to_proc to play the code block role.
>>
>> In the case of a lambda, to_proc just returns the receiver. So you can
>> do:
>>
>>    array.map &lambda {|x| x * 10 }
> It might be interesting to note that in Ruby1.9 the to_proc is not
> called on Proc objects, I wonder what happened in 1.8

I guess it's an optimization. So take my explanation as behavioral
rather than implementation-faithful.


David

-- 
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