disallow specified syntax (no-restricted-syntax)

禁止使用特定的语法 (no-restricted-syntax)

JavaScript has a lot of language features, and not everyone likes all of them. As a result, some projects choose to disallow the use of certain language features altogether. For instance, you might decide to disallow the use of try-catch or class, or you might decide to disallow the use of the in operator.

JavaScript 有很多语言特征,并不是每个人都喜欢所有的特征。因此,一些项目选择完全禁用某些特定的语言特征。例如,你可以禁止 try-catchclass 的使用,或者你可以决定是否禁用 in 操作符。

You can also specify AST selectors to restrict, allowing much more precise control over syntax patterns.

你也可以指定AST 选择器来进行限制,允许对语法模式进行更精确的控制。

Rule Details

This rule disallows specified (that is, user-defined) syntax.

该规则禁止使用特定的(由用户来指定)语法。

Options

This rule takes a list of strings, where each string is an AST selector:

该规则有一个选项,是个字符串列表,列表中的每个字符串都是一个 AST 选择器。

{
    "rules": {
        "no-restricted-syntax": ["error", "FunctionExpression", "WithStatement", "BinaryExpression[operator='in']"]
    }
}

Alternatively, the rule also accepts objects, where the selector and an optional custom message are specified:

另外,该规则还接受对象作为选项,指定选择器和可选的自定义消息:

{
    "rules": {
        "no-restricted-syntax": [
            "error",
            {
                "selector": "FunctionExpression",
                "message": "Function expressions are not allowed."
            },
            {
                "selector": "CallExpression[callee.name='setTimeout'][arguments.length!=2]",
                "message": "setTimeout must always be invoked with two arguments."
            }
        ]
    }
}

If a custom message is specified with the message property, ESLint will use that message when reporting occurrences of the syntax specified in the selector property.

如果使用 message 属性指定了一个自定义消息,ESLint 在报告 selector 属性中指定的语法时将使用该消息。

The string and object formats can be freely mixed in the configuration as needed.

字符串选项和对象格式的选项可以自由的根据需要混合使用。

Examples of incorrect code for this rule with the "FunctionExpression", "WithStatement", BinaryExpression[operator='in'] options:

选项 "FunctionExpression", "WithStatement", BinaryExpression[operator='in']错误 代码示例:

/* eslint no-restricted-syntax: ["error", "FunctionExpression", "WithStatement", "BinaryExpression[operator='in']"] */

with (me) {
    dontMess();
}

var doSomething = function () {};

foo in bar;

Examples of correct code for this rule with the "FunctionExpression", "WithStatement", BinaryExpression[operator='in'] options:

选项 "FunctionExpression", "WithStatement"正确 代码示例:

/* eslint no-restricted-syntax: ["error", "FunctionExpression", "WithStatement", "BinaryExpression[operator='in']"] */

me.dontMess();

function doSomething() {};

foo instanceof bar;

When Not To Use It

If you don’t want to restrict your code from using any JavaScript features or syntax, you should not use this rule.

如果你不想限制你的代码使用 JavaScript 任何的特征或语法,不应使用此规则。

Version

This rule was introduced in ESLint 1.4.0.

该规则在 ESLint 1.4.0 中被引入。

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