Home » PHP » PHP_Compat » Bug #8208

[2006-07-13 14:19 UTC] giunta dot gaetano at sea-aeroportimilano dot it

Description:
------------
Maybe not the most important function in the world, but I found a very old install of PHP 4.0.4 hanging around (in production!), so I whipped up a replacement. Here it is, complete w. unit test

<?php
/**
* Replace function is_callable()
*
* @category PHP
* @package PHP_Compat
* @link http://php.net/function.is_callable
* @author Gaetano Giunta <giunta.gaetano@sea-aeroportimilano.it>
* @version $Revision: 0.1 $
* @since PHP 4.0.6
* @require PHP 4.0.0 (true, false, etc...)
* @todo add the 3rd parameter syntax...
*/
if (!function_exists('is_callable')) {
function is_callable($var, $syntax_only=false)
{
if ($syntax_olny)
{
/* from The Manual:
* 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
*/
return (is_string($var) || (is_array($var) && count($var) == 2 && is_string(end($var)) && (is_string(reset($var)) || is_object(reset($var)))));
}
else
{
if (is_string($var))
{
return function_exists($var);
}
else if (is_array($var) && count($var) == 2 && is_string($method = end($var)))
{
$obj = reset($var);
if (is_string($obj))
{
$methods = get_class_methods($obj);
return (bool)(is_array($methods) && in_array(strtolower($method), $methods));
}
else if (is_object($obj))
{
return method_exists($obj, $method);
}
}
return false;
}
}
}

?>

Test script:
---------------
include('is_callable.php');
include('xmlrpc.inc');
$a = new xmlrpcval('hello world');

var_dump(is_callable(1));
var_dump(is_callable(false));
var_dump(is_callable(array('xmlrpcval', 'serialize', 'me')));
var_dump(is_callable(array('xmlrpcvaz', 'serialize')));
var_dump(is_callable(array('xmlrpcval', 'serializez')));
var_dump(is_callable(array($a, 'serializez')));
var_dump(is_callable(array($a, 'serialize', 'me')));

var_dump(is_callable('is_callable'));
var_dump(is_callable('is_cAllable'));
var_dump(is_callable(array('xmlrpcval', 'serialize')));
var_dump(is_callable(array('Xmlrpcval', 'serialize')));
var_dump(is_callable(array('Xmlrpcval', 'Serialize')));
var_dump(is_callable(array($a, 'serialize')));
var_dump(is_callable(array($a, 'Serialize')));

Expected result:
----------------
(tested against php 4.4...)

bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)