Maybe you could use Text::Balanced instead? (in particular extract_bracketed())

Module::CoreList says it's a core module since: 

$ corelist Text::Balanced

Text::Balanced was first released with perl 5.007003

[download]

(IOW, for 5.6 you'd have an additional dependency...)

In reply to Re: Extracting a parenthesized fragment from a string by almut
in thread Extracting a parenthesized fragment from a string by fce2

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