no-arrow-condition

在需要测试条件的地方禁止使用箭头函数。

¥Disallows arrow functions where test conditions are expected.

箭头函数 (=>) 在语法上类似于一些比较运算符（>、<、<= 和 >=）。此规则警告不要在需要条件的地方使用箭头函数语法。即使箭头函数的参数用括号封装，这条规则仍然会触发警告。

¥Arrow functions (=>) are similar in syntax to some comparison operators (>, <, <=, and >=). This rule warns against using the arrow function syntax in places where a condition is expected. Even if the arguments of the arrow function are wrapped with parens, this rule still warns about it.

这是一个示例，其中 => 的用法很可能是一个错字：

¥Here’s an example where the usage of => is most likely a typo:

// This is probably a typo
if (a => 1) {}
// And should instead be
if (a >= 1) {}
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在某些情况下，=> 的用法可能会模棱两可，应重写以更清楚地表明作者的意图：

¥There are also cases where the usage of => can be ambiguous and should be rewritten to more clearly show the author’s intent:

// The intent is not clear
var x = a => 1 ? 2 : 3
// Did the author mean this
var x = function (a) { return a >= 1 ? 2 : 3 }
// Or this
var x = a <= 1 ? 2 : 3
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规则详情

¥Rule Details

此规则的错误代码示例：

¥Examples of incorrect code for this rule:

/*eslint no-arrow-condition: "error"*/

if (a => 1) {}
while (a => 1) {}
for (var a = 1; a => 10; a++) {}
a => 1 ? 2 : 3
(a => 1) ? 2 : 3
var x = a => 1 ? 2 : 3
var x = (a) => 1 ? 2 : 3
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相关规则

• arrow-parens
• no-confusing-arrow
• no-constant-condition

版本

此规则是在 ESLint v1.8.0 中引入，并在 v2.0.0-beta.3 中删除。