<?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 decorator(callable $decorator)
{
// This function replaces 'trace'
return function($wrapped) use ($decorator) {
// This function replaces the function which 'trace' is used on.
return function() use ($wrapped, $decorator) {
var_dump($wrapped);
$arguments = func_get_args();
return call_user_func($decorator, $wrapped, $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 $decorator;
}
function trace() {
return decorate(['decorator'], function() {
printf("Calling %s with arguments %s\n", print_r($fn, true), print_r($arguments, true));
return call_user_func_array($fn, $arguments);
}, func_get_args());
}
function foo()
{
return decorate(['trace'], function() {
echo "Hello World\n";
}, func_get_args());
}
function bar()
{
return decorate(
[returns('string')],
function() {
return "foo";
},
func_get_args()
);
}
foo();
bar();
preferences:
35.14 ms | 402 KiB | 5 Q