Doc #53908 [NEW]: String comparison by == and ===

From: Operating system: PHP version: 5.3.5 Package: Documentation problem Bug Type: Documentation Problem Bug description:String comparison by == and === Description: ------------ Currently http://www.php.net/manual/en/language.operators.comparison.php says in the table: $a == $b Equal TRUE if $a is equal to $b. $a === $b Identical TRUE if $a is equal to $b, and they are of the same type. (introduced in PHP 4) This is confusing because "1.2" == "1.20" (so "$a is equal to $b"), and they are of the same type, but "1.2" !== "1.20". In other words, the type comparison is not the only difference between == and ===, as implied by this table. I suggest rewording this to something like: $a === $b Identical TRUE if $a is identical in type and value to $b. Below it also says The type conversion does not take place when the comparison is === or !== as this involves comparing the type as well as the value. The was added due to bug 50738. However, the "as this involves" part is not important here, but again implies that the type comparison is the only difference, so I suggest removing it. A section dealing specifically with the smart string comparison would be very helpful, especially since it is different from normal string-to-number conversion ("5z" == 5 while "5z" != "5"). This could even be a separate page (like http://www.php.net/manual/en/language.oop5.object-comparison.php for objects, which is linked from the second table). Examples can come from past bugs: bug 1974, bug 23110, bug 25763, bug 25943, bug 39084, bug 43304. -- Edit bug report at http://bugs.php.net/bug.php?id=53908&edit=1 -- Try a snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=53908&r=trysnapshot52 Try a snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=53908&r=trysnapshot53 Try a snapshot (trunk): http://bugs.php.net/fix.php?id=53908&r=trysnapshottrunk Fixed in SVN: http://bugs.php.net/fix.php?id=53908&r=fixed Fixed in SVN and need be documented: http://bugs.php.net/fix.php?id=53908&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=53908&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=53908&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=53908&r=needscript Try newer version: http://bugs.php.net/fix.php?id=53908&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=53908&r=support Expected behavior: http://bugs.php.net/fix.php?id=53908&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=53908&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=53908&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=53908&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=53908&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=53908&r=dst IIS Stability: http://bugs.php.net/fix.php?id=53908&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=53908&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=53908&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=53908&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=53908&r=mysqlcfg