From: dblack@...
Date: 2006-08-08T22:36:54+09:00
Subject: Re: value of $1is retained

Hi --

On Tue, 8 Aug 2006, Anders Vesterberg wrote:

> Hi
> I am using regexp in a loop to extract a value from a
> string. I have noticed that when string is nil $1 keeps its
> old value, which means that the expression after regexp
> does not get the correct value (which should be nil). The
> code looks like this
>
> (0..key_colnames.length-1).each do |i|
>  person_data[key_colnames[i]] =~ /\"?([\w\-: ]*)\"?/
>  # assigning $1 to something
> end
>
> Shouldn't the $-variables be reset after each regexp? Or is
> it a better way to do this?

If you're calling =~ on nil, no match operation takes place.
Object#=~ returns false, and NilClass doesn't override it.


David

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