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no-this-before-super

Disallow this/super before calling super() in constructors

Recommended

The "extends": "eslint:recommended" property in a configuration file enables this rule

在派生类的构造函数中,如果 this/supersuper() 调用之前被使用,会引发引用错误。

本规则检查构造函数中的 this/super 关键字,然后报告那些在 super() 之前的关键字。

规则细节

这条规则的目的是在调用 super() 之前标记 this/super 关键字。

示例

使用此规则的错误示例:

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/*eslint no-this-before-super: "error"*/
/*eslint-env es6*/

class A extends B {
    constructor() {
        this.a = 0;
        super();
    }
}

class A extends B {
    constructor() {
        this.foo();
        super();
    }
}

class A extends B {
    constructor() {
        super.foo();
        super();
    }
}

class A extends B {
    constructor() {
        super(this.foo());
    }
}

使用此规则的正确示例:

Open in Playground
/*eslint no-this-before-super: "error"*/
/*eslint-env es6*/

class A {
    constructor() {
        this.a = 0; // OK, this class doesn't have an `extends` clause.
    }
}

class A extends B {
    constructor() {
        super();
        this.a = 0; // OK, this is after `super()`.
    }
}

class A extends B {
    foo() {
        this.a = 0; // OK. this is not in a constructor.
    }
}

何时不用

如果你不想被通知在构造函数的 super() 前使用 this/super,你可以安全地禁用这一规则。

Handled by TypeScript

It is safe to disable this rule when using TypeScript because TypeScript's compiler enforces this check.

Version

This rule was introduced in ESLint v0.24.0.

Resources

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