ID: 13439
Updated by: [EMAIL PROTECTED]
Reported By: [EMAIL PROTECTED]
Status: Open
-Bug Type: Regexps related
+Bug Type: Documentation problem
Operating System: linux 2.2.19
PHP Version: 4.2.1
New Comment:
So it goes...
Previous Comments:
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[2002-06-08 13:13:22] [EMAIL PROTECTED]
AFAIK, POSIX re's have no concept of non-greedy quantifiers.
All quantifiers are greedy. But even supposing that this
were a possibility i.e. the * quntifier is non-greedy, the following
needs explaining:
1) Why the difference between + and * ?
2) ereg_replace('.*','b','aa') should produce an _infinite_
string of b's because the minimum match is the empty string
and the global ('g' modified) behavior means that there are
an infinity of minimum matches available.
3) ereg_replace('.*c','b','aac') should produce 'ab' but it
doesn't, it produces just 'b'. In other words, the addition
of the 'c' following the * quantifier has changed the
behaviour from non-greedy to greedy!
There is no consistent explanation available for this
behaviour. The behaviour is just plain wrong!
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[2002-06-08 08:32:59] [EMAIL PROTECTED]
I think this can be documentation issue - or a bug.
Remember that ereg(i)_replace functions are always 'g' modified. So
that would make it the issue, whether * is greedy.
By nature + is greedy (cause otherwise the 'or more' wouldn't make
sence), but if it's considered, that * isn't greedy, than what php does
is perfectly correct as each 'a' matches .*.
It would at least be consistent if they we're both greedy as .*? isn't
supported and you can't turn of the global behavior.
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[2002-06-08 07:50:27] [EMAIL PROTECTED]
I'm running linux 2.2.19. I've also tested php 4.0.4pl1
running on linux 2.4.2 and the behaviour is the same.
------------------------------------------------------------------------
[2002-06-07 16:48:57] [EMAIL PROTECTED]
Updated the version..which OS are you running PHP on?
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[2002-06-07 14:48:36] [EMAIL PROTECTED]
Derick!
This _is_ a bug! I've now upgraded to 4.2.1 and the
behaviour remains the same. Consider just these two:
ereg_replace('.+','b','aa') -> b
ereg_replace('.*','b','aa') -> bb
and this from man 7 regex:
"An atom followed by `*' matches a sequence
of 0 or more matches of the atom. An atom followed
by `+' matches a sequence of 1 or more matches of
the atom."
How can it NOT be a bug?
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The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
http://bugs.php.net/13439
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Edit this bug report at http://bugs.php.net/?id=13439&edit=1
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