spaced-line-comment

Enforces consistent spacing after // in line comments.

Some style guides require or disallow a whitespace immediately after the initial // of a line comment. Whitespace after the // makes it easier to read text in comments. On the other hand, commenting out code is easier without having to put a whitespace right after the //.

Rule Details

This rule will enforce consistency of spacing after the start of a line comment //.

This rule takes two arguments. If the first is "always" then the // must be followed by at least once whitespace. If "never" then there should be no whitespace following. The default is "always".

The second argument is an object with one key, "exceptions". The value is an array of string patterns which are considered exceptions to the rule. It is important to note that the exceptions are ignored if the first argument is "never". Exceptions cannot be mixed.

Examples of incorrect code for this rule:

// When ["never"]
// This is a comment with a whitespace at the beginning
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//When ["always"]
//This is a comment with no whitespace at the beginning
var foo = 5;
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// When ["always",{"exceptions":["-","+"]}]
//------++++++++
// Comment block
//------++++++++
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Examples of correct code for this rule:

// When ["always"]
// This is a comment with a whitespace at the beginning
var foo = 5;
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//When ["never"]
//This is a comment with no whitespace at the beginning
var foo = 5;
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// When ["always",{"exceptions":["-"]}]
//--------------
// Comment block
//--------------
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// When ["always",{"exceptions":["-+"]}]
//-+-+-+-+-+-+-+
// Comment block
//-+-+-+-+-+-+-+
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Related Rules

• spaced-comment

Version

This rule was introduced in ESLint v0.9.0 and removed in v1.0.0-rc-1.