From: Christopher Causer <chy.causer@...>
Date: 2008-02-12T18:10:56+09:00
Subject: Re: Return number of matches

William James wrote:
> On Feb 11, 8:41 am, Jano Svitok <jan.svi...@gmail.com> wrote:
>> Easy solution: count $ and subtract \$ ;-)
>>
>> string.scan(/\$/).size - string.scan(/\\\$/).size
>>
>> It's possible to do it in one regex, but it won't be nice and elegant
>> and I don't have the time now to try it...
> 
> That fails when the backslash preceding a $
> is itself escaped.
> 
>>> irb --prompt xmp
> string = "$\\\\$"
>     ==>"$\\\\$"
> string.scan(/\$/).size - string.scan(/\\\$/).size
>     ==>1

Erm, not sure what you're trying to say. One is the answer I would have 
wanted. Thanks anyway for the one liner though.

Just out of interest, why doesn't my first effort work?

string.scan(/[^\\]\$/).size

?
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