CMemCache bug

There is issue with CMemCache cache, for example there is no checking in MemCache init function idf extension is not loaded, like it is done for other cache extensions.

So, there should be code like:




public function init()

	{

		parent::init();

		if(!extension_loaded('memcache'))

			throw new CException(Yii::t('yii','CMemCache requires PHP memcache extension to be loaded.'));

        ...

        ...

	}



There is no need to duplicate the same content here an on github issue - https://github.com/yiisoft/yii/issues/578