always check if a class has been previously loaded ?

Generally, $this->load->xyz() and $this->lang->load() are fairly intelligent about checking whether something has been loaded. For example, if you're loading a language file which has previously been loaded, it won't be reloaded. However, if you're loading a language file which was loaded previously under a different language, it will reload the file for the new language.

However, you may be able to perform a more efficient check in your code than that used by the method in question and save yourself a small amount of time for subsequent calls to load the same model or library. It's not necessarily worth the effort, because $this->load->model() and $this->load->library() should never cause any problems by being called for a model or library which has already been loaded, but it could make a small difference in extreme cases.

Bonfire

Practical CodeIgniter 3
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