note 24806 added to language.types.boolean
| From: | php-general at lists dot php dot net | Date: | Thu, 29 Aug 2002 01:56:04 +0000 |
| Subject: | note 24806 added to language.types.boolean | ||
| Groups: | php.notes | ||
| Request: | Send a blank email to php-notes+get-35952@lists.php.net to get a copy of this message | ||
Despite 1 and 2 can both be converted to a boolean as TRUE, they differ:
(1 == TRUE) will be true
(2 == TRUE) will be false!
In an expression with ==, where there's a numeric value and a boolean, the boolean is promoted
to the numeric type and the values are compared.
So never perform tests based on the equivalent numeric value of TRUE. Don't write:
if ($variable == TRUE)...
as the condition would be false if the variable contains something else than a TRUE boolean, or a
numeric value different of 1. Simply write:
if ($variable)...
or:
if (!empty($variable))...
--
http://www.php.net/manual/en/language.types.boolean.php
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