Re: substitution with exceptions

Looks like you want a Negative Lookbehind Assertion:

(?<!foo) Negative Lookbehind Asserts that what immediately precedes the current position in the string is not foo

maybe try s/(?<!\bisn)(?<!\baren)'t/ 't/g

\b ensures a word boundary.

(actually in order to play save you should also check for a trailing boundary 't\b

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

Wikisyntax for the Monastery
FootballPerl is like chess, only without the dice}

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Re^2: substitution with exceptions by choroba (Cardinal) on Sep 27, 2018 at 19:27 UTC
Negative look-behind only works for fixed length patterns, "aren" and "isn" are of different lengths. `(?<!n)'t` [download] might work, but if you need to exclude both, you can't use `(?<!aren\|isn)'t Variable length lookbehind not implemented in regex m/(?<!aren\|isn)'t/` [download] You can specify them one by one, though: `(?<!aren)(?<!isn)'t` [download] ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]
Re^3: substitution with exceptions by LanX (Saint) on Sep 27, 2018 at 19:45 UTC
Tsk, you replied to the king of updates without checking ? ;-p Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^2: substitution with exceptions by haukex (Archbishop) on Sep 27, 2018 at 19:31 UTC
Looks good :-) (Note: Link requires a fairly modern browser)	[reply]
Re^2: substitution with exceptions by Anonymous Monk on Sep 27, 2018 at 20:08 UTC
WOW. It works perfectly.	[reply]