require or disallow newlines around variable declarations (one-var-declaration-per-line)

要求或禁止在变量声明周围换行 (one-var-declaration-per-line)

The --fix option on the command line can automatically fix some of the problems reported by this rule.

命令行中的 --fix 选项可以自动修复一些该规则报告的问题。

Some developers declare multiple var statements on the same line:

一些开发者在同一行上声明多个变量:

var foo, bar, baz;

Others prefer to declare one var per line.

另一些人更喜欢声明每个变量单独成行。

var foo,
    bar,
    baz;

Keeping to one of these styles across a project’s codebase can help with maintaining code consistency.

在整个项目中保持使用一种风格有利于保持代码一致性。

Rule Details

This rule enforces a consistent newlines around variable declarations. This rule ignores variable declarations inside for loop conditionals.

该规则强制变量声明使用一致的的换行。该规则忽略 for 循环语句中的变量声明。

Options

This rule has a single string option:

该规则有一个字符串选项,可以是:

initializations

Examples of incorrect code for this rule with the default "initializations" option:

默认选项 "initializations"错误 代码示例:

/*eslint one-var-declaration-per-line: ["error", "initializations"]*/
/*eslint-env es6*/

var a, b, c = 0;

let a,
    b = 0, c;

Examples of correct code for this rule with the default "initializations" option:

默认选项 "initializations"正确 代码示例:

/*eslint one-var-declaration-per-line: ["error", "initializations"]*/
/*eslint-env es6*/

var a, b;

let a,
    b;

let a,
    b = 0;

always

Examples of incorrect code for this rule with the "always" option:

选项 "always"错误 代码示例:

/*eslint one-var-declaration-per-line: ["error", "always"]*/
/*eslint-env es6*/

var a, b;

let a, b = 0;

const a = 0, b = 0;

Examples of correct code for this rule with the "always" option:

选项 "always"正确 代码示例:

/*eslint one-var-declaration-per-line: ["error", "always"]*/
/*eslint-env es6*/

var a,
    b;

let a,
    b = 0;

Version

This rule was introduced in ESLint 2.0.0-beta.3.

该规则在 ESLint 2.0.0-beta.3 中被引入。

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