A christmas wish: simple notation for ratcheting (non-backtrack) regex

I know... I can already say (?= ... ) to prevent
backtracking once committed.

But it occurred to me the other day that just like
"?" following a quantifier
(?, *, +, , {m,n}) was formerly illegal, and therefore
used to introduce
the notion of laziness, that "+" is likewise
illegal.  How about making it so
that any quantifier (including lazily modified quantifers)
followed by "+"
means "never backtrack"?

So /a.*+b/ (or /a.{0,}+b/) would mean the same as /a(?=.*)b/
and /a.*?+b/ (or /a.{0,}?+b/) would mean the same as
/a(?=.*?)b/
and /a.++b/ (or /a.{1,}+b/) would means the same as
/a(?=.+)b/

Same functionality, just a much nicer notation.
"+" means "once I've
committed, that's it!".

Just a thought.

-- 
Randal L. Schwartz - Stonehenge Consulting Services, Inc. -
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On Mon, Dec 25, 2006 at 12:28:01PM -0800, Randal L. Schwartz
wrote:
> But it occurred to me the other day that just like
"?" following a quantifier
> (?, *, +, , {m,n}) was formerly illegal, and
therefore used to introduce
> the notion of laziness, that "+" is likewise
illegal.  How about making it so
> that any quantifier (including lazily modified
quantifers) followed by "+"
> means "never backtrack"?
> ...
> Same functionality, just a much nicer notation.
"+" means "once I've
> committed, that's it!".

Are you asking for the same thing as the Java
"possessive quantifiers"?
They use "+" to mean this already.

Cheers,
mark

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