no-useless-concat

禁止不必要的字面或模板字面串联

没有必要将两个字符串连接在一起,例如:

var foo = "a" + "b";

此代码可能是从串联中删除变量的重构结果(例如 "a" + b + "b")。在这种情况下,串联并不重要,代码可以重写为:

var foo = "ab";

规则详情

此规则旨在标记 2 个字面的连接,当它们可以组合成一个字面时。字面可以是字符串或模板字面。

此规则的错误代码示例:

/*eslint no-useless-concat: "error"*/
/*eslint-env es6*/

var a = `some` + `string`;

// these are the same as "10"
var a = '1' + '0';
var a = '1' + `0`;
var a = `1` + '0';
var a = `1` + `0`;

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/*eslint no-useless-concat: "error"*/

// when a non string is included
var c = a + b;
var c = '1' + a;
var a = 1 + '1';
var c = 1 - 2;
// when the string concatenation is multiline
var c = "foo" +
    "bar";

何时不使用

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