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Eslint参考手册

规则 | Rules

operator-assignment

在命令行上的--fix选项可以自动修复一些被这条规则反映的问题。

JavaScript 提供了结合变量赋值和一些简单的数学运算的速记运算符。例如,x = x + 4可以缩短为x += 4。支持的简写形式如下:

Shorthand | Separate
-----------|------------
 x += y    | x = x + y
 x -= y    | x = x - y
 x *= y    | x = x * y
 x /= y    | x = x / y
 x %= y    | x = x % y
 x <<= y   | x = x << y
 x >>= y   | x = x >> y
 x >>>= y  | x = x >>> y
 x &= y    | x = x & y
 x ^= y    | x = x ^ y
 x |= y    | x = x | y

规则细节

在可能的情况下,此规则要求或不允许赋值运算符速记。

选项

该规则具有单个字符串选项:

  • "always" (默认)在可能的情况下需要赋值运算符速记
  • "never" 不允许赋值运算符速记

always

此规则的默认"always"选项错误代码示例:

/*eslint operator-assignment: ["error", "always"]*/

x = x + y;
x = y * x;
x[0] = x[0] / y;
x.y = x.y << z;

具有默认"always"选项的此规则的正确代码示例:

/*eslint operator-assignment: ["error", "always"]*/

x = y;
x += y;
x = y * z;
x = (x * y) * z;
x[0] /= y;
x[foo()] = x[foo()] % 2;
x = y + x; // `+` is not always commutative (e.g. x = "abc")

never

此规则的错误代码示例包含以下"never"选项:

/*eslint operator-assignment: ["error", "never"]*/

x *= y;
x ^= (y + z) / foo();

此规则的正确代码示例包含以下"never"选项:

/*eslint operator-assignment: ["error", "never"]*/

x = x + y;
x.y = x.y / a.b;

何时不使用它

操作员的使用分配速记是一种文体选择。如果关闭此规则,开发人员可以根据具体情况选择哪种风格更具可读性。

版本

该规则在 ESLint 0.10.0中引入。

资源

  • 规则资源
  • 文档资源

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1.accessor-pairs
2.array-bracket-newline
3.array-bracket-spacing
4.array-callback-return
5.array-element-newline
6.arrow-body-style
7.arrow-parens
8.arrow-spacing
9.block-scoped-var
10.block-spacing
11.brace-style
12.callback-return
13.camelcase
14.capitalized-comments
15.class-methods-use-this
16.comma-dangle
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19.complexity
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21.consistent-return
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26.dot-location
27.dot-notation
28.eol-last
29.eqeqeq
30.for-direction
31.func-call-spacing
32.func-name-matching
33.func-names
34.func-style
35.function-paren-newline
36.generator-star
37.generator-star-spacing
38.getter-return
39.global-require
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42.handle-callback-err
43.id-blacklist
44.id-length
45.id-match
46.implicit-arrow-linebreak
47.indent
48.indent-legacy
49.init-declarations
50.jsx-quotes
51.key-spacing
52.keyword-spacing
53.line-comment-position
54.linebreak-style
55.lines-around-comment
56.lines-around-directive
57.lines-between-class-members
58.max-depth
59.max-len
60.max-lines
61.max-nested-callbacks
62.max-params
63.max-statements
64.max-statements-per-line
65.multiline-comment-style
66.multiline-ternary
67.new-cap
68.new-parens
69.newline-after-var
70.newline-before-return
71.newline-per-chained-call
72.no-alert
73.no-array-constructor
74.no-arrow-condition
75.no-await-in-loop
76.no-bitwise
77.no-buffer-constructor
78.no-caller
79.no-case-declarations
80.no-catch-shadow
81.no-class-assign
82.no-comma-dangle
83.no-compare-neg-zero
84.no-cond-assign
85.no-confusing-arrow
86.no-console
87.no-const-assign
88.no-constant-condition
89.no-continue
90.no-control-regex
91.no-debugger
92.no-delete-var
93.no-div-regex
94.no-dupe-args
95.no-dupe-class-members
96.no-dupe-keys
97.no-duplicate-case
98.no-duplicate-imports
99.no-else-return
100.no-empty
Eslint

ESLint 是一个代码规范和错误检查工具,有以下几个特性。所有东西都是可以插拔的。你可以调用任意的 rule api 或者 formatter api 去打包或者定义 rule or formatter。任意的 rule 都是独立的。没有特定的 coding style,你可以自己配置。

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1.指南 | Guide
2.规则 | Rules