<?php
function decorate(array $decorators, callable $fn, array $arguments = array())
{
foreach (array_reverse($decorators) as $decorator) {
if (is_callable($decorator)) {
$fn = $decorator($fn);
}
}
return call_user_func_array($fn, $arguments);
}
function expects(/* $type,... */)
{
$types = func_get_args();
$decorator = function(callable $fn) use ($types) {
$wrapper = function() use ($fn, $types) {
foreach (func_get_args() as $i => $arg) {
if (($type = gettype($arg)) !== $types[$i] and isset($types[$i]) and $types[$i] !== 'mixed') {
throw new \InvalidArgumentException("Expected type of argument $i to be {$types[$i]}, got $type");
}
}
return call_user_func_array($fn, func_get_args());
};
return $wrapper;
};
return $decorator;
}
function returns($type)
{
$decorator = function($fn) use ($type) {
$wrapper = function() use ($fn, $type) {
$returnValue = call_user_func_array($fn, func_get_args());
if (($returnType = gettype($returnValue)) !== $type) {
throw new \UnexpectedValueException("Expected return type $type, got $returnType");
}
return $returnValue;
};
return $wrapper;
};
return $decorator;
}
function bar()
{
return decorate(
[
expects('integer'),
returns('string')
],
function($foo) {
return "foo";
},
func_get_args()
);
}
bar(0);
bar("foo");
preferences:
35.72 ms | 402 KiB | 5 Q