Re^2: Using negative lookahead

"Unfortunately regexes don't support backreferences in character classes - like [^\g1] - to forbid the delimiter inside the string. (at least I couldn't find it.)"

I wouldn't think that would work in the general case, where \g1 refers to more than one character, would it?

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Re^3: Using negative lookahead by LanX (Saint) on Oct 20, 2017 at 14:01 UTC
depends what you mean with the general case. Do you mean ... ... `[^\g1]` with \g1 more than one letter? This is hypothetical, since even one letter doesn't work. ... `( (?! \g1) .)` This Would disallow a multibyte sequence if the match holds a word. I.e. like the word "not" to be forbidden to follow ... `( (?! \g1) (?! \g2) .)` Here chaining look-aheads work like AND conditions. For single bytes, this would be equivalent of `[^\g1\g2]` (if it was possible) you might be interested this excellent tutorial Using Look-ahead and Look-behind Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply] [d/l] [select]

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Re^3: Using negative lookahead
by LanX (Saint) on Oct 20, 2017 at 14:01 UTC

Do you mean ...

... [^\g1] with \g1 more than one letter?

... ( (?! \g1) .)*

I.e. like the word "not" to be forbidden to follow

... ( (?! \g1) (?! \g2) .)*

For single bytes, this would be equivalent of [^\g1\g2] (if it was possible)

you might be interested this excellent tutorial

Using Look-ahead and Look-behind

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)

Je suis Charlie!}

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