Confusing use of "function declaration" in describing default parameters

> **[Alternative default parameters](https://javascript.info/function-basics#alternative-default-parameters)**
> Sometimes it makes sense to assign default values for parameters at a later stage after the function declaration.
> ...
> ```js run
> function showMessage(text) {
> // ...
>
> if (text === undefined) { // if the parameter is missing
> text = 'empty message';
> }
>
> alert(text);
> }
>
> showMessage(); // empty message
> ```

The declaration includes the function definition. Saying "after the function declaration" suggests something happening after the entirety of the function when the description refers to something happening later in the body.

打开链接的 Alternative default parameters 部分，检查示例周围的措辞。修改对 "function declaration" 的引用，使其准确描述函数体内后续的赋值，然后检查周围的说明是否仍然清晰。

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