From: Pit Capitain <pit@...>
Date: 2006-07-13T01:39:21+09:00
Subject: Re: Help with a regexp

Daniel Schierbeck schrieb:
> I'm trying to write a regular expression that matches bencoded strings, 
> i.e. strings on the form x:y, where x is the numeric length of y.
> 
> This is valid:
> 
>   6:foobar
> 
> while this is not:
> 
>   4:foo
> 
> I've tried using #{$1} inside the regexp, but it seems $1 is still nil 
> at that point. Here's what I've got so far:
> 
>   /^([1-9]+\d*):(\w){#{$1}}$/
> 
> (it ain't working)
> 
> I'm matching with `string =~ regexp'; would it be better if I did it 
> another way?

Daniel, I'm pretty sure you can't do it with a single regexp test. Why 
not split the test in two parts, as in

   str =~ /^([1-9]\d*):(\w+)$/ && $2.size == $1.to_i

Regards,
Pit