Free

Free.php

<?php

class Free
{
    const A = 0x1;
    const B = 0x2;
    const C = 0x4;

    protected $typeList;

    protected $free = 0;

    protected function isFlag($flag) {
        if (is_null($this->typeList)) {
            $reflector = new ReflectionClass($this);
            $this->typeList = $reflector->getConstants();
        }

        if (!in_array($flag, $this->typeList)) {
            throw new Exception('Error constant ' . $flag . ' undefined');
        }

        return true;
    }

    public function isFreeFor($flag) {
        $this->isFlag($flag);
        return $this->free & $flag;
    }

    public function makeFreeFor($flag) {
        $this->isFlag($flag);
        $this->free |= $flag;
    }

    public function makeUnfreeFor($flag) {
        $this->isFlag($flag);
        $this->free &= ~$flag;
    }

    public function resetFree() {
        $this->free = 0;
    }
}

$f = new Free;
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::A);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::B);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::C);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->resetFree();
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::A);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::B);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor(Free::C);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeUnFreeFor(Free::A);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeUnFreeFor(Free::B);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeUnFreeFor(Free::C);
var_dump($f->isFreeFor(Free::A));
var_dump($f->isFreeFor(Free::B));
var_dump($f->isFreeFor(Free::C));
$f->makeFreeFor('A');