From:             johnston dot joshua at gmail dot com
Operating system: OS X 10.5.2
PHP version:      5.2.5
PHP Bug Type:     Strings related
Bug description:  Escape sequences being expanded in single quoted strings

Description:
------------
This is either a bug with strings or a documentation bug depending on what
you decide is "The PHP Way"

When using backslashes in single quoted strings, a double backslash is
being interpreted as the escape sequence for a single backslash. This is
contrary to what the php manual leads you to believe.

The php manual for single quoted strings (php.net/types.string) says:

To specify a literal single quote, you will need to escape it with a
backslash (\), like in many other languages. If a backslash needs to occur
before a single quote or at the end of the string, you need to double it.
Note that if you try to escape any other character, the backslash will also
be printed! So usually there is no need to escape the backslash itself.

It is my opinion that since escape sequences do not work inside single
quoted strings that backslashes should exhibit the same behavior.

e.g
'\'' is a single quote
'\' is a parse error
'\ ' is a backslash followed by a space
'\\' is a single backslash
'\\ ' is two backslashes followed by a space

I understand that this is a difficult issue that a backslash is sometimes
an escape sequence and sometimes not. If this cannot be accomplished then
the php manual should be updated to reflect this "gotcha".

I did notice a few similar reports regarding this issue and I believe that
some clarification should be added.

Reproduce code:
---------------
<?php
echo '\ 1', PHP_EOL;
echo '\\ 2', PHP_EOL;
echo '\\\ 3', PHP_EOL;
echo '\\\\ 4', PHP_EOL;
echo '\\\\\ 5', PHP_EOL;
echo '\\\\\\ 6', PHP_EOL;

Expected result:
----------------
\ 1
\\ 2
\\\ 3
\\\\ 4
\\\\\ 5
\\\\\\ 6

Actual result:
--------------
\ 1
\ 2
\\ 3
\\ 4
\\\ 5
\\\ 6

-- 
Edit bug report at http://bugs.php.net/?id=44397&edit=1
-- 
Try a CVS snapshot (PHP 5.2): 
http://bugs.php.net/fix.php?id=44397&r=trysnapshot52
Try a CVS snapshot (PHP 5.3): 
http://bugs.php.net/fix.php?id=44397&r=trysnapshot53
Try a CVS snapshot (PHP 6.0): 
http://bugs.php.net/fix.php?id=44397&r=trysnapshot60
Fixed in CVS:                 http://bugs.php.net/fix.php?id=44397&r=fixedcvs
Fixed in release:             
http://bugs.php.net/fix.php?id=44397&r=alreadyfixed
Need backtrace:               http://bugs.php.net/fix.php?id=44397&r=needtrace
Need Reproduce Script:        http://bugs.php.net/fix.php?id=44397&r=needscript
Try newer version:            http://bugs.php.net/fix.php?id=44397&r=oldversion
Not developer issue:          http://bugs.php.net/fix.php?id=44397&r=support
Expected behavior:            http://bugs.php.net/fix.php?id=44397&r=notwrong
Not enough info:              
http://bugs.php.net/fix.php?id=44397&r=notenoughinfo
Submitted twice:              
http://bugs.php.net/fix.php?id=44397&r=submittedtwice
register_globals:             http://bugs.php.net/fix.php?id=44397&r=globals
PHP 4 support discontinued:   http://bugs.php.net/fix.php?id=44397&r=php4
Daylight Savings:             http://bugs.php.net/fix.php?id=44397&r=dst
IIS Stability:                http://bugs.php.net/fix.php?id=44397&r=isapi
Install GNU Sed:              http://bugs.php.net/fix.php?id=44397&r=gnused
Floating point limitations:   http://bugs.php.net/fix.php?id=44397&r=float
No Zend Extensions:           http://bugs.php.net/fix.php?id=44397&r=nozend
MySQL Configuration Error:    http://bugs.php.net/fix.php?id=44397&r=mysqlcfg

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