note 27666 added to function.is-callable

From: Date: Sat, 14 Dec 2002 23:48:06 +0000
Subject: note 27666 added to function.is-callable
Groups: php.notes 
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is_callable -- Verify that the contents of a variable can be called as a function. bool is_callable ( mixed var [, bool syntax_only [, string callable_name]]) Verify that the contents of a variable can be called as a function. This can check that a simple variable contains the name of a valid function, or that an array contains a properly encoded object and function name. The var parameter can be either the name of a function stored in a string variable, or an object and the name of a method within the object, like this: array( $SomeObject, 'MethodName' ). If the syntax_only argument is true the function only verifies that var might be a function or method. It will only reject simple variables that are not strings, or an array that does not have a valid structure to be used as a callback. The valid ones are supposed to have only 2 entries, the first of which is an object or a string, and the second a string. The callable_name argument receives the "callable name". In the example below it's "someClass::someMethod". Note, however, that despite the implication that someClass::SomeMethod() is a callable static method, this is not the case. #!/usr/local/bin/php -q <? php // How to check a variable to see if it can be called // as a function. // // Simple variable containing a function // function someFunction() { } $functionVariable = 'someFunction'; var_dump( is_callable( $functionVariable, false, $callable_name )); // bool(true) echo $callable_name, "\n"; // someFunction // // Array containing a method // class someClass { function someMethod() { } } $anObject = new someClass(); $methodVariable = array( $anObject, 'someMethod' ); var_dump( is_callable( $methodVariable, true, $callable_name )); // bool(true) echo $callable_name, "\n"; // someClass:someMethod ?> -- http://www.php.net/manual/en/function.is-callable.php http://master.php.net/manage/user-notes.php?action=edit+27666 http://master.php.net/manage/user-notes.php?action=delete+27666 http://master.php.net/manage/user-notes.php?action=reject+27666

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