From: Robert Dober <robert.dober@...>
Date: 2008-12-11T18:54:58+09:00
Subject: Re: lambda with $1 fails as gsub block

On Thu, Dec 11, 2008 at 12:18 AM, Mike Gold <mike.gold.4433@gmail.com> wrote:

> Apparently $1 is bound in a peculiar way:
Not really, it somehow the proc object that is evaluated "first"
def meth(replace)
   ">x".gsub(%r!(\W)x!)do
   puts "$1 is #{$1.inspect}"
   end
 end
and
def meth(replace)
   ">x".gsub(%r!(\W)x!, &replace)
  p $1
 end

work as expected

You will clearly see what I mean with the following example

def meth(replace)
   ">x".gsub(%r!(\W)x!, &replace)
 end

 replace = lambda { |match|
   puts "last_match is #{Regexp.last_match.inspect}"
 }
which produces

last_match is #<MatchData "">

Interesting stuff
Robert




>
>  http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/e24a19e6ea75e5de/0211d0b304cbbad0?hl=en%C3%93d0b304cbbad0
>
> Matz suggested that the MatchData could have been passed to the block
> for convenience, however it looks more like a necessity, as I don't see
> a solution short of rewriting gsub.
>
> This suggests that for 1.9, MatchData should be passed as an optional
> second argument to the block.  Yes?
> --
> Posted via http://www.ruby-forum.com/.
>
>



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