src/Container/Container.php
protected function value($name)
    {
        $object = isset($this->instances[$name]) ? $this->get($name) : null;

        $exists = ! $object && $this->extra->has($name) === true;

        return $exists === true ? $this->extra->get($name) : $object;
    }
protected function value($name)
    {
        $object = isset($this->instances[$name]) ? $this->get($name) : null;

        $exists = ! $object && $this->extra->has($name) === true;

        return $exists === true ? $this->extra->get($name) : $object;
    }
Returns the value of the specified argument.

@param  string $name
@return mixed|null