ID:               39901
 User updated by:  schizoduckie at gmail dot com
 Reported By:      schizoduckie at gmail dot com
 Status:           Bogus
 Bug Type:         Variables related
 Operating System: Win32/XP
 PHP Version:      5CVS-2006-12-20 (snap)
 New Comment:

I have had a little discussion here, in dutch
(http://gathering.tweakers.net/forum/list_messages/1185071) with some
other programmers who also wanted to reply on this thread but couldn't
because it's marked bogus. I'd just like this to be noted and added to
the thread though:

--- Quote -NME-  --- 

Quite frankly, your excuse is kind of weak. Yes, switch uses the same
semantics as the == operator. Yes, this means possible unwanted
conversions (which, for the life of me, I don't understand - "0123" is
a string; which, compared to "123" is _not_ the same. If I'd wanted it
to be the same, I'd have defined it as 0123 and 123 respectively). But
if you actually explicitly cast the variable to a string, I think it
should do a strict comparison.

PHP invites you to use strange code, very strange code indeed. For
instance, the following returns true:
PHP:
        
<?php
$a = 0;
$b = "foo";

if ($a == $b)
    echo "PHP sucks";
?>

Idiotic inconsistencies like this one and the workarounds experienced
programmers have to write just to make the language easy to work with
for beginners really damage your reputation and the PHP language in
general.

Do with this comment as you please, but I really think you should
provide experienced programmers with more means of keeping their code
tidy and clean, without dumb workarounds.

--- end quote --


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

[2006-12-20 13:43:06] [EMAIL PROTECTED]

It does not matter whether you cast the variables or not, switch()
always uses semantics similar to "==".
Again, there is nothing wrong and we're not going to change it.

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

[2006-12-20 13:34:25] schizoduckie at gmail dot com

I disagree with this bug being bogus.

Once you start giving people the power of casting, this type of
programming should be either consistently be possible to use throughout
the PHP or be completely removed to avoid any misunderstandings.

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

[2006-12-20 13:25:29] schizoduckie at gmail dot com

I agree that this is expected behavior for loosly typed variables. but
i am CASTING explicity to String because i want it to be treated as
string, which should trigger the switch to work as ===

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

[2006-12-20 13:20:45] [EMAIL PROTECTED]

switch() construct uses "==" semantics to compare values, which
compares numeric strings as numbers:
var_dump("0123"=="123"); => true

If you want to compare numeric strings as strings, use "===":
var_dump("0123"==="123"); => false.

This is expected behaviour.

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

[2006-12-20 13:16:41] schizoduckie at gmail dot com

Description:
------------
In a switch, a value that is declared as string with a prefix 0 will
automatically disappear in switched values, even if all of them are
specifically casted as a string.

Reproduce code:
---------------
$field = (string)"0123";
settype($field, 'string'); // just to make sure, for testcase

switch ($field) 
{
    case '123': $result = 'first'; break;
    case '456': $result = 'second'; break;
        default: $result = 'third'; break;
}

echo $result; // first, due to string / int conversion.

switch ((string)$field) // explicit cast to string
{
    case (string)'123': $result = 'first'; break; // more (unneccesary
casts just to be sure)
    case (string)'456': $result = 'second'; break;
        default: $result = 'third'; break;
}

echo $result; // first! ????


Expected result:
----------------
I would have expected the last result echo to be third because of the
explicit typecasting.

This problem appears in all php versions up to 5.2 snapshot of today.

Actual result:
--------------
the code in the example speaks for itself.


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


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