ID: 23110
Updated by: [EMAIL PROTECTED]
Reported By: kyrael at web dot de
-Status: Open
+Status: Closed
Bug Type: Documentation problem
Operating System: Linux
PHP Version: 4.3.1
New Comment:
This bug has been fixed in the documentation's XML sources. Since the
online and downloadable versions of the documentation need some time
to get updated, we would like to ask you to be a bit patient.
Thank you for the report, and for helping us make our documentation
better.
"If you compare integer with the string, the string is converted to
number. If you compare two numerical strings, they are compared as
integers. These rules are valid also for the switch statement." +
example:
<?php
var_dump(0 == "a"); // 0 == 0 -> true
var_dump("1" == "01"); // 1 == 1 -> true
switch ("a") {
case 0:
echo "0";
break;
case "a": // never reached because "a" is already matched with 0
echo "a";
break;
}
?>
Previous Comments:
------------------------------------------------------------------------
[2004-05-22 11:20:55] [EMAIL PROTECTED]
See also #20726.
------------------------------------------------------------------------
[2004-02-04 18:15:12] tgrey at supercomputerinc dot com
highly illogical indeed. if the types differ, how could the values be
considered equal? when working with functions that could have
different input types this behaviour is disasterous. it seems to be
counterproductive to loose variable types, since a data type check has
to be added.
working around is often possible, but if i wanted to code around my ***
to get to my elbow i'd be using perl. imho this behavior needs some
strong reconsideration.
very simple example:
<?
$in="blah";
if($in==0)
echo "zero: $in";
else
echo "not zero: $in";
?>
or worse yet:
<?
function test($in=0)
{
switch($in)
{
case 0:
echo "zero: $in";
break;
case "blah": // never reached!
echo "blah: $in";
break;
default:
echo "default: $in";
break;
}
}
test();
test("blah");
test(2);
?>
------------------------------------------------------------------------
[2003-05-02 13:10:29] [EMAIL PROTECTED]
This will not change, the documentation team needs to be clear on
that.
We don't have '===' for nothing.
------------------------------------------------------------------------
[2003-04-08 06:57:38] kyrael at web dot de
Btw, in switch you can't use strcmp or ===, because switch seems to use
==.
------------------------------------------------------------------------
[2003-04-08 06:43:46] kyrael at web dot de
<?php
list($var1,$var2)=array("1e1","10");
var_dump($var1);var_dump($var2);
var_dump($var1==$var2);
var_dump($var1===$var2);
?>
string(3) "1e1"
string(2) "10"
bool(true)
bool(false)
This behaviour is ugly - both operands are strings, and they are
clearly not equal. '1e0' and '1.0' and '1' are "equal" too. Same with
'3.20' and '3.2'. Does PHP think i am stupid and unable to type numbers
when i want them?
According to the manual, == returns true if the two operands are equal,
and === returns true if the operands are equal and of the same type. ==
says they are equal, and according to var_dump they are both strings -
why doesn't === return true then? So this behaviour is neither logical
nor documented. String comparison, even with == when both operands are
strings, should return 'equal' if and only if the strings are really
equal. Wouldn't be PHP5 a chance to change this?
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=23110&edit=1
