The let function has several possible options, as does the declare function to which it is closely related.

let函数具有几个可用的选项，可以执行与它密切关联的declare函数。

youdao

There may be pitfalls when you use long long types for function arguments, unless you declare function prototypes.

如果不声明函数原型，使用long long类型作为函数的参数可能会引起一些意想不到的错误。

youdao

In the module, I declare a function of this type to deal with the incoming data.

在这个模块中，我们声明了一个这种类型的函数来处理到达的数据。

youdao

If you scroll back up on the printout or screen here, you'll see that you can actually not only declare function's prototypes, their general structure.

如果我回滚到打印输出或者这个屏幕，你们将看到你们不仅可以声明函数的原型,它们的一般结构。

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So now, henceforth, when you say, to declare a function, I am declaring a function here but down here am I quote unquote defining it or implementing it.

从此以后，当你说，声明一个函数，我在这里声明了一个函数,但是到这里我定义它或执行它。

哈佛公开课 - 计算机科学课程节选

And when you declare a variable, whether as an argument or as literally a local variable, they only live inside of that function.

当你声明一个变量，不论是一个参数,还是一个局部变量，它们只存在函数的内部。

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