In PHP, does the class use server resources if it does not instantiate? Solution Ideas

In PHP, does the class use server resources if it does not instantiate?
In PHP, does the class use server resources if it does not instantiate? Because I want to create a file, put all the classes in a file, when needed to include this file

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When the class file is loaded, PHP will compile the class
When a class is instantiated, PHP allocates memory to the corresponding object
When the object executes, PHP allocates memory for the property involved

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I don't think so, but the problem is relative, although you don't instantiate it, but it brings a new problem.

Include n classes of documents and include 1 classes of documents which do you think Occupy server resources? Of course, this occupancy can be ignored.

You can do this, but I'm not recommending that you do this from the maintenance and readability of the code will only bring you more trouble. The last reminder is whether you use __autoload if not then follow your thoughts.

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