Re^2: How to enforce match priority irrespective of string position

And that method worked! (Though I've had to restructure a bit to accommodate, as that was not in a simple substitution form.) I don't mind doing whatever is necessary to get things working, though...so thank you very much! I'll certainly upvote this when I get my next day's rations.

This part seems to be the crucial bit: (?=Point|\z) (?!\1). I find this sort of syntax confusing because it always seems to me that the "Point" here should have precedence over anything coming afterward in the regex sequence, in this case the "\1" backreference. If "Point" is already detected from the forward assertion, why can it be matched again (overlapped) by this reference, even if in the negative?

Well, no complaints at the moment, certainly, as at least the script is now past this hurdle. Thank you.

Blessings,

~Polyglot~

Comment on Re^2: How to enforce match priority irrespective of string position

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Re^3: How to enforce match priority irrespective of string position by tybalt89 (Monsignor) on Mar 08, 2021 at 02:25 UTC
Because (?= and (?! are ZERO-WIDTH assertions.	[reply]
Re^4: How to enforce match priority irrespective of string position by Polyglot (Chaplain) on Mar 08, 2021 at 02:37 UTC
I appreciate knowing that, but while the assertion may be "zero-width," my mind still stumbles on the point that "Point" is certainly not zero-width. I'd always understood the "zero-width" aspect to be more related to the capturing and positioning of the match within the string. Are all look-arounds zero-width? If so, why must a look-behind be always of a specified length (width) that is not variable? Well, it may be that it's just too abstract for me. Thank you for your explanation. Blessings, ~Polyglot~	[reply]
Re^5: How to enforce match priority irrespective of string position by eyepopslikeamosquito (Archbishop) on Mar 08, 2021 at 03:30 UTC
This reference explains it quite well: lookaround actually matches characters, but then gives up the match, returning only the result: match or no match. That is why they are called “assertions”. They do not consume characters in the string, but only assert whether a match is possible or not. ... most regex flavors do not allow you to use just any regex inside a lookbehind, because they cannot apply a regular expression backwards. The regular expression engine needs to be able to figure out how many characters to step back before checking the lookbehind. Hope that helps.	[reply]


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