Explain how template tags are interpreted by an expert

Explain how the template label is explained
I recently learned how to write a custom label, but I do not understand the principle of TP parsing templates and labels, I hope to have a master to point out the process of specific analysis, such as $this->assign () is how to work, display is called those classes and methods of these, The internet for a long time have no results ... template? Tags

------Solution--------------------
Watch the lib/core/view.class.php file under thinkphp

In fact, there is no need to learn more, especially beginners
You know, that's the way it is.

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