#41496 [Asn->Bgs]: Preg_Split returns 3 matches with offset -1
| From: | nlopess@php.net | Date: | Mon, 28 May 2007 15:53:58 +0000 |
| Subject: | #41496 [Asn->Bgs]: Preg_Split returns 3 matches with offset -1 | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-113108@lists.php.net to get a copy of this message | ||
ID: 41496
Updated by: nlopess@php.net
Reported By: m_v_ at gmx dot net
-Status: Assigned
+Status: Bogus
Bug Type: PCRE related
Operating System: Windows Vista Home Premium
PHP Version: 5CVS-2007-05-25 (snap)
Assigned To: nlopess
New Comment:
in this case we only use the information that is passed from PCRE. The
extra entries you are seeing appear because of the backtracking
algorithms (used in current regex engines).
You can always skip those results by specifying the PREG_SPLIT_NO_EMPTY
flag.
Previous Comments:
------------------------------------------------------------------------
[2007-05-25 09:57:53] m_v_ at gmx dot net
Description:
------------
preg_split behaves unexpectet with certain pattern (see reproduce
code):
It returns tripple offsets with the offsetvalue -1.
It gets even worse when you replace:
$reg = "~\{(literal)\}(.*?)\{(/literal)\}|\{(.*?)\}~s";
with
$reg = "~\{\*(literal)\}(.*?)\{(/literal)\}|\{(.*?)\}~s";
it simply returns several off those empty string, offset -1 triples.
P.S.: Hope it is actually a bug and not my ignorance of regex, however
i asked in a forum if anybody knew where the mistake is and i got no
answer and in addition the offset -1 mykes it look like a bug to me.
If it however should be a mistake in my regex it would be kind if you
would let me know how to put it.
Thx in advance
Reproduce code:
---------------
$reg = "~\{(literal)\}(.*?)\{(/literal)\}|\{(.*?)\}~s";
echo $reg.'<br>';
$res = preg_split( $reg, "df{g}s{literal}asd{as}d{/literal}", -1,
PREG_SPLIT_DELIM_CAPTURE|PREG_SPLIT_OFFSET_CAPTURE );
echo '<pre>'.print_r($res, 1).'</pre>';
Expected result:
----------------
~\{(literal)\}(.*?)\{(/literal)\}|\{(.*?)\}~s
Array
(
[0] => Array
(
[0] => df
[1] => 0
)
[1] => Array
(
[0] => g
[1] => 3
)
[2] => Array
(
[0] => s
[1] => 5
)
[3] => Array
(
[0] => literal
[1] => 7
)
[4] => Array
(
[0] => asd{as}d
[1] => 15
)
[5] => Array
(
[0] => /literal
[1] => 24
)
[6] => Array
(
[0] =>
[1] => 33
)
)
Actual result:
--------------
~\{(literal)\}(.*?)\{(/literal)\}|\{(.*?)\}~s
Array
(
[0] => Array
(
[0] => df
[1] => 0
)
[1] => Array
(
[0] =>
[1] => -1
)
[2] => Array
(
[0] =>
[1] => -1
)
[3] => Array
(
[0] =>
[1] => -1
)
[4] => Array
(
[0] => g
[1] => 3
)
[5] => Array
(
[0] => s
[1] => 5
)
[6] => Array
(
[0] => literal
[1] => 7
)
[7] => Array
(
[0] => asd{as}d
[1] => 15
)
[8] => Array
(
[0] => /literal
[1] => 24
)
[9] => Array
(
[0] =>
[1] => 33
)
)
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=41496&edit=1