public function hasSingleton($class, $checkInstance = false)
    {
        $class = $this->getAlias($class);

        return $checkInstance ? isset($this->_singletons[$class]) : array_key_exists($class, $this->_singletons);
    }
public function hasSingleton($class, $checkInstance = false)
    {
        $class = $this->getAlias($class);

        return $checkInstance ? isset($this->_singletons[$class]) : array_key_exists($class, $this->_singletons);
    }
public function hasSingleton ( $ class , $ checkInstance = false ) { $ class = $ this -> getAlias ( $ class ) ; return $ checkInstance ? isset ( $ this -> _singletons [ $ class ] ) : array_key_exists ( $ class , $ this -> _singletons ) ; }
Returns a value indicating whether the given name corresponds to a registered singleton.
@param string $class class name, interface name or alias name
@param boolean $checkInstance whether to check if the singleton has been instantiated.
@return boolean whether the given name corresponds to a registered singleton. If `$checkInstance` is true,
the method should return a value indicating whether the singleton has been instantiated.
Returns a value indicating whether the given name corresponds to a registered singleton .