Hi sm@sh,

I'm not quite sure I understand yet, could you provide some more context? Are you trying to determine whether a regex had capture groups or not? If so, how about this?

"1" =~ /1/;
print @->1?"yes\n":"no\n";
"1" =~ /(1)/;
print @->1?"yes\n":"no\n";
__END__
no
yes

[download]

This uses the special variable @-, aka @LAST_MATCH_START.

Update 2018-09-01: Actually, @+ will give you the number of capture groups! See my reply below for the difference.

Regards,
-- Hauke D

In reply to Re^3: How can I test for the representation of an integer? (updated!) by haukex
in thread How can I test for the representation of an integer? by sm@sh

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