I am using 5.3.10 and trying to create closures in following manner, but it gives parse error. Can anyone tell me why it is giving parse error?
class ABC {
public static $funcs = array(
'world' => function() {
echo "Hello,";
echo "World!\n";
},
'universe' => function() {
echo "Hello,";
echo "Universe!\n";
},
);
}
The reason why this is not working is that in PHP it is not allowed to assign a closure directly to a (static) class variable initializer.
So for your code to work, you have to use this workaround:
<?php
class ABC {
public static $funcs;
}
ABC::$funcs = array(
'world' => function() {
echo "Hello,";
echo "World!\n";
},
'universe' => function() {
echo "Hello,";
echo "Universe!\n";
},
);
$func = ABC::$funcs['world'];
$func();
The workaround is taken from the answer to this question on Stack Overflow: PHP: How to initialize static variables
Btw, notice that it is also not possible to call the function directly via ABC::$funcs['world'](). For this to work you would have to use PHP >= 5.4 which introduced function array dereferencing.
Static properties can only be initialized using literals or constants. From the PHP manual at http://php.net/manual/en/language.oop5.static.php:
Like any other PHP static variable, static properties may only be initialized using a literal or constant; expressions are not allowed. So while you may initialize a static property to an integer or array (for instance), you may not initialize it to another variable, to a function return value, or to an object.
