It ACTS like a macro in this context, where calling the method of function via the closure makes the function call in the context of where it's defined.

它在此上下文中用作宏，通过闭包调用函数方法将在定义它的上下文中执行函数调用。

youdao

However, we can set up a closure at the beginning of the function to keep the string from having to be passed on each call.

不过，我们可以在函数的起始处设置一个闭包(closure)，以使得不再必须为每一个调用都传递那个字符串。

youdao

Variables to be imported from the outside environment are specified in the use clause of the closure function definition.

从外部环境中导入的变量是在闭包函数定义的use子句中指定的。

youdao