Looks to me like $1 is always going to be defined. It just may be empty. Maybe what you want is (\{)? to match the open brace, very much like the example in perlre.

-- Randal L. Schwartz, Perl hacker

In reply to Re: Regex conditional match if previous match in same expression is true? by merlyn
in thread Regex conditional match if previous match in same expression is true? by radiantmatrix

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