merlyn's code uses the feature of list assignment in scalar context. This returns the number of elements being returned, which, in this case, is either 0 or 2. If the regex matches, then it returns $1 and $2, which means that $base and $ext get their values.

If the regex matches, then the two variables have values -- one can not be defined if the other isn't. Thus, merlyn's code does the right thing.

japhy -- Perl and Regex Hacker

In reply to (japhy) Re: Re: Re: regex for assignment by japhy
in thread regex for assignment by mkmcconn

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