public function whatProvides($name, LinkConstraintInterface $constraint = null, $mustMatchName = false)
    {
        $key = ((int) $mustMatchName).$constraint;
        if (isset($this->providerCache[$name][$key])) {
            return $this->providerCache[$name][$key];
        }

        return $this->providerCache[$name][$key] = $this->computeWhatProvides($name, $constraint, $mustMatchName);
    }