http://www.perlmonks.org?node_id=560365


in reply to Re: An optimization of last resort: eliminate capturing from your regexps
in thread An optimization of last resort: eliminate capturing from your regexps

Just so you know... $1 et all are basically ties that do something like

substr($something, $-[$digit], $+[$digit] - $-[$digit]);

Part of the reason for this is that internally perl doesnt populate $1 et all with copies when it runs the regex as when backtracking it could have to recopy the contents of these vars many many times. Wheras updating the appropriate offsets is cheap and constant time.

---
$world=~s/war/peace/g

Replies are listed 'Best First'.
Re^3: An optimization of last resort: eliminate capturing from your regexps
by diotalevi (Canon) on Jul 11, 2006 at 13:15 UTC

    They're not actually ties though. Ties are slow, these aren't.

    ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊