Oops, missed that.

Still the principle that merlyn stated is correct, and is a common performance mistake in parsing. Try it with a 1 MB string. If substr still wins then I guarantee you that someone implemented a buffering strategy with strings and substr where doing a destructive substr at the beginning of a string just moves indexes around and does not recopy.

Perl plays a lot of games like that, for instance that is why push, pop and friends are fast. I am just a little surprised to see it played on strings...

In reply to Re (tilly) 8: how do I line-wrap while copying to stdout? by tilly
in thread how do I line-wrap while copying to stdout? by ams

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