Re: Failed regex: negative look-behinds

Thus spaketh the doc perlre

       "(?<!pattern)"
                 A zero-width negative look-behind assertion.  For exa
+mple
                 "/(?<!bar)foo/" matches any occurrence of "foo" that 
+does not
                 follow "bar".  Works only for fixed-width look-behind
+.
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Therefore, /\A(?<!compiled)[a-zA-Z0-9]+\z/ matches any occurance of one or more alphanumeric at the end of a string that does not follow "compiled"

You might also have an issue with operator associativity and/or precedence... from perlop, orhas much lower precedence (and left associativity) than eq...

--chargrill

$/  =  q#(\w)#  ;  sub  sig { print scalar reverse  join  ' ',  @_  } 
+ sig
map { s$\$/\$/$\$2\$1$g && $_ } split( ' ', ",erckha rlPe erthnoa stJu
+" );
[download]

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Re^2: Failed regex: negative look-behinds by loikiolki (Novice) on Feb 07, 2006 at 06:04 UTC
therefore, /\A(?<!compiled)[a-zA-Z0-9]+\z/ matches any occurance of one or more alphanumeric at the end of a string that does not follow "compiled" Which is exactly what I want to match, but the regex doesn't seem to match this any occurance of one or more alphanumeric at the end of a string that does not follow "compiled". shrug	[reply]
Re^3: Failed regex: negative look-behinds by chargrill (Parson) on Feb 07, 2006 at 06:11 UTC
I think they're right up above, most notably ikegami and graff... the entire OP regex is anchored at start-of-string, so there's no place to "look-behind" --chargrill `$/ = q#(\w)# ; sub sig { print scalar reverse join ' ', @_ } + sig map { s$\$/\$/$\$2\$1$g && $_ } split( ' ', ",erckha rlPe erthnoa stJu +" );` [download]	[reply] [d/l]