src/Tomahawk/DependencyInjection/Container.php
public function offsetExists($id)
    {
        if ($this->hasAlias($id)) {
            $id = $this->getAlias($id);
        }

        return isset($this->keys[$id]);
    }
public function offsetExists($id)
    {
        if ($this->hasAlias($id)) {
            $id = $this->getAlias($id);
        }

        return isset($this->keys[$id]);
    }
Checks if a parameter or an object is set.

@param string $id The unique identifier for the parameter or object

@return bool