Modifying a string's value resets pos.
That's not in the doc that I've seen -- "perldoc -f pos" doesn't show it, and it doesn't seem to be anywhere in the ORA Programming Perl book (3rd Ed.). So, how do you know this? Experimentation? Looking at the source? Whatever the answer, I still think there should be a definitive spec as to what progressive matching covers.

I would think that s/// is in the same family as m// simply because matching has to be done "exactly the same way" -- it could even be considered a convenience function. Therefore, I would say that 'progressive matching'for s/// should follow the same rules that m// does in while() loops.

And that brings us back to pos and my question about how you know that pos resets to 0 if the string is modified. If it's *specified* to do that, that's one thing--but if it's just an artifact of implementation (ie., it's not formally documented as a spec), then I'd say it could be changed, and s/// could then become compliant (and consistent) with existing specs. dan

Dan Heller
http://www.danheller.com

In reply to Re^6: Progressive matching w/substitutions (pos) by argv
in thread Progressive matching w/substitutions by argv

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