From: Josh Cheek <josh.cheek@...>
Date: 2010-11-27T12:50:12+09:00
Subject: Re: Newbie: two cool discoveries

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On Fri, Nov 26, 2010 at 6:45 PM, w_a_x_man <w_a_x_man@yahoo.com> wrote:

> On Nov 26, 8:11 am, Arturo Garcia <arturo.g.art...@gmail.com> wrote:
> > the "&" is a shortcut to "to_proc"
> >
> > class Symbol
> >   def to_proc
> >     lambda { |x| x.__send__(self) }
>
> Note that it's to_proc, not to_lambda. I don't see why
> anyone would want to type the gibberish "lambda" when
> he could type the shorter and clearer "proc".
>
>
Because lambda is more pretentious (at least, thats why I use it)

They actually have different meanings, though (sometimes)



$ cat proc_vs_lambda.rb
def invoke_lambda
  lambda { return 1 }.call
  return 2
end

def invoke_proc
  proc { return 1 }.call
  return 2
end

require 'pp'
puts ENV['RUBY_VERSION']
puts invoke_lambda # => 2
puts invoke_proc   # => 1
puts



$ rvm proc_vs_lambda.rb
jruby-1.5.3
2
2

macruby-0.7
2
1

rbx-1.1.0-20100923
2
2

ruby-1.8.6-p399
2
2

ruby-1.8.7-p302
2
2

ruby-1.9.1-p378
2
1

ruby-1.9.2-p0
2
1

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