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Eslint参考手册

规则 | Rules

newline-after-var

--fix命令行上的选项可以自动修复一些被这条规则反映的问题。

此规则在ESLint v4.0.0 中已弃用,并由填充行间语句规则取代。

从今天起,在将变量声明与其他代码分离时没有一致性。有些开发人员在var语句和其他代码之间留下了一条空行,如下所示:

var foo;

// do something with foo

而其他人根本没有留下任何空白的换行符。

var foo;
// do something with foo

问题在于这些开发人员在一个项目中一起工作。此规则强制执行,其中空换行符允许或禁止后一种编码风格varletconst语句。它有助于代码在整个项目中保持一致。

规则细节

此规则强制执行,其中空线都需要或禁止后一种编码风格varletconst语句来实现整个项目一致的编码风格。

选项

这条规则有一个字符串选项:

  • "always"(默认)需要后一个空行varletconst 在一条线上评论之后直接变种语句被当作附加的变种语句。
  • "never"不允许空行之后varletconst

always

此规则的默认代码错误代码示例"always"

/*eslint newline-after-var: ["error", "always"]*/
/*eslint-env es6*/

var greet = "hello,",
    name = "world";
console.log(greet, name);

let greet = "hello,",
    name = "world";
console.log(greet, name);

var greet = "hello,";
const NAME = "world";
console.log(greet, NAME);

var greet = "hello,";
var name = "world";
// var name = require("world");
console.log(greet, name);

具有默认选项的此规则的正确代码示例"always"

/*eslint newline-after-var: ["error", "always"]*/
/*eslint-env es6*/

var greet = "hello,",
    name = "world";

console.log(greet, name);

let greet = "hello,",
    name = "world";

console.log(greet, name);

var greet = "hello,";
const NAME = "world";

console.log(greet, NAME);

var greet = "hello,";
var name = "world";
// var name = require("world");

console.log(greet, name);

never

此规则的错误代码示例包含以下"never"选项:

/*eslint newline-after-var: ["error", "never"]*/
/*eslint-env es6*/

var greet = "hello,",
    name = "world";

console.log(greet, name);

let greet = "hello,",
    name = "world";

console.log(greet, name);

var greet = "hello,";
const NAME = "world";

console.log(greet, NAME);

var greet = "hello,";
var name = "world";
// var name = require("world");

console.log(greet, name);

此规则的正确代码示例包含以下"never"选项:

/*eslint newline-after-var: ["error", "never"]*/
/*eslint-env es6*/

var greet = "hello,",
    name = "world";
console.log(greet, name);

let greet = "hello,",
    name = "world";
console.log(greet, name);

var greet = "hello,";
const NAME = "world";
console.log(greet, NAME);

var greet = "hello,";
var name = "world";
// var name = require("world");
console.log(greet, name);

版本

此规则在ESLint 0.18.0中引入。

资源

  • 规则来源
  • 文档来源

规则 | Rules相关

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
17.comma-spacing
18.comma-style
19.complexity
20.computed-property-spacing
21.consistent-return
22.consistent-this
23.constructor-super
24.curly
25.default-case
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
40.global-strict
41.guard-for-in
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-before-return
70.newline-per-chained-call
71.no-alert
72.no-array-constructor
73.no-arrow-condition
74.no-await-in-loop
75.no-bitwise
76.no-buffer-constructor
77.no-caller
78.no-case-declarations
79.no-catch-shadow
80.no-class-assign
81.no-comma-dangle
82.no-compare-neg-zero
83.no-cond-assign
84.no-confusing-arrow
85.no-console
86.no-const-assign
87.no-constant-condition
88.no-continue
89.no-control-regex
90.no-debugger
91.no-delete-var
92.no-div-regex
93.no-dupe-args
94.no-dupe-class-members
95.no-dupe-keys
96.no-duplicate-case
97.no-duplicate-imports
98.no-else-return
99.no-empty
100.no-empty-character-class
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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2.规则 | Rules