From: David Alan Black <dblack@...>
Date: 2001-08-09T21:49:44+09:00
Subject: [ruby-talk:19424] Re: Setting $_ for the current scope

Hello --

On Thu, 9 Aug 2001, Dave Thomas wrote:

> Renald Buter <buter@CWTS.LeidenUniv.nl> writes:
>
> > Looking back at my question, I see it is a bit fuzzy. What I am
> > really looking for is a case-like structure _with_ fall-through, but
> > _without_ having to write down the variable name for each regexp
> > test.
>
> Possibly the Ruby case statement might help :)
>
>   case bla
>   when /help/ then help
>   when /exit/ then exit
>   else
>     puts "Sorry"
>   end
>
> And not a $_ in sight.

I think Renald wanted the possibility of more than one statement
executing.  In his Perl-esque example:

>        bla = "help_more"
>        for bla
>                # $_ is now equal to bla ("help_more")
>                /help/ and help
>                /help_more/ and help_more
>                /help_even_more/ and help_even_more
>        end

help and help_more would both happen.

One possibility would be:

  for $_ in bla
    help if /help/
    help_more if /help_more/
    help_even_more if /help_even_more/
  end

I've gotten so unused to seeing $_ :-)

Any chance that some other form of method dispatch would be
cleaner/safer?  (But that's another matter.)


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav