/**
* Creates a new ManyMaybe instance from the given collection,
* thereby composing each collection item into an Maybe monad.
*
* @param array $values
*/
protected function __construct(array $values)
{
$unit = function ($value) {
return Maybe::unit($value);
};
parent::__construct(array_map($unit, $values));
}
{
if ($value instanceof Maybe) {
return $value;
}
return new static($value);
}
// Places an object into the monad if the isNothing function returns true
public function bind(callable $function)
{
return $this->isNothing() ? $this : static::unit($function($this->container));
}
public function isNothing()
{
return $this->container === false;
}
}
// Object to test
$vehicle = new Vehicle(1, 'golf', 'red', 12000, true, 1000);
// Ruleset for type, color and mileage
$type = function ($value) {
return Maybe::unit($value->type == 'golf' ? $value : false);
};
$color = function ($value) {
return Maybe::unit($value->color == 'red' ? $value : false);
};
$mileage = function ($value) {
return Maybe::unit($value->mileage == 12000 ? $value : false);
};
// Execution. On success an object will be returned
$test = Maybe::unit($vehicle)->bind($type)->bind($color)->bind($mileage);
var_dump($test->get());
