每天laravel-20160730| Container -2

    /** * Determine if the given abstract type has been bound. * * @param string $abstract * @return bool */
    public function bound($abstract)
    {
        $abstract = $this->normalize($abstract);// the function is to delete the \ on the left if has

        return isset($this->bindings[$abstract]) || isset($this->instances[$abstract]) || $this->isAlias($abstract);
    }// Determine if the given abstract type has been bound.
    // sorry today is a lazy day.