pos doesn't apply to s/// just like it doesn't apply to pack/unpack or anything else. pos only talks about m//g and that is the only thing that it applies to.
No question about it. However, the nature of how m// and s/// appears, and how they are documented closely together, makes them appear much more closely related, which would also allow them to share this particular characteristic -- especially in the context of "progressive matching." Remember, the frame of mind that someone is in when they think "progressive" is to "match-operate-match-operate, etc." Since m// lets you do that in a while loop, it seems reasonable to (at least) suspect that maybe s/// would do it too. By contrast, one wouldn't expect to apply to pack/unpack "or anything else" (as you put it) because those functions don't look so similar. Those are conceptually different.

if nothing else, I think it warrants comment in documentation that pos can be reset if used with s///, "or any other operation that may change the string, even if that change occurs later in the string than pos points to."

FWIW, I look forward to learning about your perl module that you described. It does seem to acknowledge the need for what I suspected to be true (or "should have been true." :-)

Dan Heller
http://www.danheller.com

In reply to Re^8: Progressive matching w/substitutions (pos) by argv
in thread Progressive matching w/substitutions by argv

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