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typescript/no-unnecessary-type-constraint Suspicious

🚧 An auto-fix is planned for this rule, but not implemented at this time.

它的作用

禁止对泛型类型使用不必要的约束。

为什么这不好?

TypeScript 中的泛型类型参数(<T>)可以通过 extends 关键字来“约束”。当未提供 extends 时,类型参数默认的约束为 unknown。 因此,从 anyunknown 继承是多余的。

示例

以下是此规则的错误代码示例:

typescript
interface FooAny<T extends any> {}
interface FooUnknown<T extends unknown> {}

type BarAny<T extends any> = {};
type BarUnknown<T extends unknown> = {};

const QuuxAny = <T extends any>() => {};

function QuuzAny<T extends any>() {}
typescript
class BazAny<T extends any> {
  quxAny<U extends any>() {}
}

以下是此规则的正确代码示例:

typescript
interface Foo<T> {}

type Bar<T> = {};

const Quux = <T>() => {};

function Quuz<T>() {}
typescript
class Baz<T> {
  qux<U>() {}
}

如何使用

To enable this rule using the config file or in the CLI, you can use:

json
{
  "rules": {
    "typescript/no-unnecessary-type-constraint": "error"
  }
}
ts
import { defineConfig } from "oxlint";

export default defineConfig({
  rules: {
    "typescript/no-unnecessary-type-constraint": "error",
  },
});
bash
oxlint --deny typescript/no-unnecessary-type-constraint

版本

此规则于 v0.0.6 中加入。

参考资料