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no-non-null-asserted-nullish-coalescing

Disallow non-null assertions in the left operand of a nullish coalescing operator.

🔒

在 ESLint 配置 中扩展"plugin:@typescript-eslint/strict" 可启用此规则。

💡

此规则报告的一些问题可以通过编辑器 建议 手动修复。

?? 空值合并运行时运算符允许在处理 null 或 undefined 时提供默认值。在空值合并运算符的左操作数中使用 ! 非空断言类型运算符是多余的，很可能是程序员错误或对这两个运算符混淆的标志。

¥The ?? nullish coalescing runtime operator allows providing a default value when dealing with null or undefined. Using a ! non-null assertion type operator in the left operand of a nullish coalescing operator is redundant, and likely a sign of programmer error or confusion over the two operators.

eslint.config.mjs
export default tseslint.config({
  rules: {
    "@typescript-eslint/no-non-null-asserted-nullish-coalescing": "error"
  }
});

在线运行试试这个规则 ↗

示例​

¥Examples

foo! ?? bar;
foo.bazz! ?? bar;
foo!.bazz! ?? bar;
foo()! ?? bar;

let x!: string;
x! ?? '';

let x: string;
x = foo();
x! ?? '';
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选项​

该规则不可配置。

何时不使用它​

¥When Not To Use It

如果你的项目的类型尚未完全描述某些值是否可以为空，例如你正在过渡到 strictNullChecks，则此规则可能会产生许多错误报告。你可以考虑在这些特定情况下使用 ESLint 禁用注释，而不是完全禁用此规则。

¥If your project's types don't yet fully describe whether certain values may be nullable, such as if you're transitioning to strictNullChecks, this rule might create many false reports. You might consider using ESLint disable comments for those specific situations instead of completely disabling this rule.

进一步阅读​

¥Further Reading

'## 资源'