public function check($key, array $options = []) {
		if (!$this->isStarted() && !$this->_start()) {
			throw new RuntimeException('Could not start session.');
		}
		return function($params) {
			return Set::check($_SESSION, $params['key']);
		};
	}
public function check($key, array $options = []) {
		if (!$this->isStarted() && !$this->_start()) {
			throw new RuntimeException('Could not start session.');
		}
		return function($params) {
			return Set::check($_SESSION, $params['key']);
		};
	}
public function check ( $ key , array $ options = [ ] ) { if ( ! $ this -> isStarted ( ) && ! $ this -> _start ( ) ) { throw new RuntimeException ( 'Could not start session.' ) ; } return function ( $ params ) { return Set :: check ( $ _SESSION , $ params [ 'key' ] ) ; } ; }
Checks if a value has been set in the session.

@param string $key Key of the entry to be checked.
@param array $options Options array. Not used for this adapter method.
@return \Closure Function returning boolean `true` if the key exists, `false` otherwise.
Checks if a value has been set in the session .