ID:          25566
 Updated by:  [EMAIL PROTECTED]
 Reported By: Jared dot Williams1 at ntlworld dot com
 Status:      Open
-Bug Type:    Scripting Engine problem
+Bug Type:    Documentation problem
 PHP Version: 4.3.3
 New Comment:

See these manual pages:

http://www.php.net/switch
http://www.php.net/manual/en/types.comparisons.php

Maybe the manual should explain this a bit better.



Previous Comments:
------------------------------------------------------------------------

[2003-09-20 06:20:46] Jared dot Williams1 at ntlworld dot com

How's this for an impossibility..

echo('a' != 0 ? 'TRUE' : 'FALSE');
echo('<br />');
echo('a' ? 'TRUE' : 'FALSE');

Outputs:
FALSE
TRUE

------------------------------------------------------------------------

[2003-09-20 06:08:53] Jared dot Williams1 at ntlworld dot com

Oh erm, seems its not limited to switch either. :/

echo('a' == 0 ? 'YES' : 'NO');
Outputs: YES

echo('3a' == 3 ? 'YES' : 'NO');
Outputs: YES

echo(4 == '4a' ? 'YES' : 'NO');
Outputs: YES

Surely these cant be considered equivalent.

------------------------------------------------------------------------

[2003-09-20 05:51:09] Jared dot Williams1 at ntlworld dot com

The non-numeric string values are getting cast to integer value 0,
which then match case 0:.

$t = array(10,1,2,3,'*','+','3a', 'b');
foreach($t as $v)
        switch ($v)
        {
                case 10: echo('0'); break;
                case 1: echo('1'); break;
                case 2: echo('2'); break;
                case 3: echo('3'); break;
                case '*': echo('*'); break;
                default: echo($v); break;
        }
Outputs:
0123*+3b

as 3a gets cast to 3. so seems there is a missing a condition in the
code somewhere, to see if the switched expression can actually be a
numeric type.


Also

$t = array(10,1,2,3,'*','+','3a', 'b');
foreach($t as $v)
        switch ($v)
        {
                case 10: echo('0'); break;
                case 1: echo('1'); break;
                case 2: echo('2'); break;
                case '*': echo('*'); break;
                case '3a': echo('!!'); break;
                default: echo($v); break;
        }
?>

Outputs:
012!!*+!!b

So the case labels are getting cast too without the check.

------------------------------------------------------------------------

[2003-09-20 00:40:40] shadowfaxx at cc dot com

To add to the above, it seems that the '0' case is the culprit. If you
use the code below where '10' replaces '0', the weird behavior does not
occur:

$t = array(10,1,2,3,'*','+','a', 'b');
foreach($t as $v)
        switch ($v)
        {
                case 10: echo('0'); break;
                case 1: echo('1'); break;
                case 2: echo('2'); break;
                case 3: echo('3'); break;
                case '*': echo('*'); break;
                default: echo($v); break;
        }
OutPut: 0123*+ab


So it seems that Case 0: grabs all the cases which are of a different
data type if the case expressions are not of the same type i.e. numeric
and string.

------------------------------------------------------------------------

[2003-09-16 18:47:44] Jared dot Williams1 at ntlworld dot com

"The first 5 array" should read "The first 4 array"

------------------------------------------------------------------------

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/25566

-- 
Edit this bug report at http://bugs.php.net/?id=25566&edit=1

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