Thank you, unfortunately that works only for simple strings, not regexes. Consider: 
'bated' =~ /^bat{3}/; false
'bated' =~ /^bat/; true

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I'm trying to look at the beginning of a string to know if it can potentially match a regex, without knowing the full string. Which is of course different from making a completely different regex with substr($regex.

(Edited for bad examples)

In reply to Re^2: Regex partial/leading match by raymorris
in thread Regex partial/leading match by raymorris

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