Well, here's how I would do it; this regex will populate $1 with the sigil, and $2 with the name if it is a variable like "$foo"; in the "<foo>" case, $1 will be undef and $2 will contain the name.

/ ^ # start (?:([\$\@\*\%])|<) # leading sigil or < (\w+) # name (?(?{$1}) |> ) # if there was a leading sigil, match nothing; # otherwise, match > $ # end /x;

Another way might be to use this one:

/ ^ # start ([\$\@\*\%<]) # sigil (\w+) # name (?(?{$1 eq '<'}) >| ) # if the sigil is a '<', match the end; # otherwise match nothing $ # end /x;

This is different in that in the "<foo>" case, $1 will be '<'.

In either case, theres no real reason to capture $3, since there is only one possibility that it could be(>), and you will know if the possibility is true or not depending on $1.


In reply to Re: conditional match in regex by jryan
in thread conditional match in regex by John M. Dlugosz

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