96 lines
2.5 KiB
PHP
96 lines
2.5 KiB
PHP
<?php
|
|
|
|
function curry($callable)
|
|
{
|
|
if (_number_of_required_params($callable) === 0) {
|
|
return _make_function($callable);
|
|
}
|
|
if (_number_of_required_params($callable) === 1) {
|
|
return _curry_array_args($callable, _rest(func_get_args()));
|
|
}
|
|
return _curry_array_args($callable, _rest(func_get_args()));
|
|
}
|
|
|
|
function _curry_array_args($callable, $args, $left = true)
|
|
{
|
|
return function () use ($callable, $args, $left) {
|
|
if (_is_fullfilled($callable, $args)) {
|
|
return _execute($callable, $args, $left);
|
|
}
|
|
$newArgs = array_merge($args, func_get_args());
|
|
if (_is_fullfilled($callable, $newArgs)) {
|
|
return _execute($callable, $newArgs, $left);
|
|
}
|
|
return _curry_array_args($callable, $newArgs, $left);
|
|
};
|
|
}
|
|
|
|
function _number_of_required_params($callable)
|
|
{
|
|
if (is_array($callable)) {
|
|
$refl = new \ReflectionClass($callable[0]);
|
|
$method = $refl->getMethod($callable[1]);
|
|
return $method->getNumberOfRequiredParameters();
|
|
}
|
|
$refl = new \ReflectionFunction($callable);
|
|
return $refl->getNumberOfRequiredParameters();
|
|
}
|
|
|
|
function _make_function($callable)
|
|
{
|
|
if (is_array($callable))
|
|
return function() use($callable) {
|
|
return call_user_func_array($callable, func_get_args());
|
|
};
|
|
return $callable;
|
|
}
|
|
|
|
function _execute($callable, $args, $left)
|
|
{
|
|
if (! $left) {
|
|
$args = array_reverse($args);
|
|
}
|
|
$placeholders = _placeholder_positions($args);
|
|
if (0 < count($placeholders)) {
|
|
$n = _number_of_required_params($callable);
|
|
if ($n <= _last($placeholders[count($placeholders) - 1])) {
|
|
throw new \Exception('Argument Placeholder found on unexpected position!');
|
|
}
|
|
foreach ($placeholders as $i) {
|
|
$args[$i] = $args[$n];
|
|
array_splice($args, $n, 1);
|
|
}
|
|
}
|
|
return call_user_func_array($callable, $args);
|
|
}
|
|
|
|
function _placeholder_positions($args)
|
|
{
|
|
return array_keys(array_filter($args, '_is_placeholder'));
|
|
}
|
|
|
|
function _is_fullfilled($callable, $args)
|
|
{
|
|
$args = array_filter($args, function($arg) {
|
|
return ! _is_placeholder($arg);
|
|
});
|
|
return count($args) >= _number_of_required_params($callable);
|
|
}
|
|
|
|
function _is_placeholder($arg)
|
|
{
|
|
return $arg instanceof Placeholder;
|
|
}
|
|
|
|
function _rest(array $args)
|
|
{
|
|
return array_slice($args, 1);
|
|
}
|
|
|
|
function product($a, $b)
|
|
{
|
|
return $a * $b;
|
|
}
|
|
|
|
echo json_encode(array_map(curry('product', 7), [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]));
|