Same way that I have multiplication or division as a primitive, functions are going to give me, or somebody else who wrote them for me as part of a library, a new primitive that I'm going to be able to use.

我在用乘法或者除法当做原语,这些函数,或者别人写程序库中的函数,将会给我返回一个,我能使用的新原语。

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