eslint/docs/rules/space-infix-ops.md

   1 # require spacing around infix operators (space-infix-ops)
   2
   3 While formatting preferences are very personal, a number of style guides require spaces around operators, such as:
   4
   5 ```js
   6 var sum = 1 + 2;
   7 ```
   8
   9 The proponents of these extra spaces believe it make the code easier to read and can more easily highlight potential errors, such as:
  10
  11 ```js
  12 var sum = i+++2;
  13 ```
  14
  15 While this is valid JavaScript syntax, it is hard to determine what the author intended.
  16
  17 ## Rule Details
  18
  19 This rule is aimed at ensuring there are spaces around infix operators.
  20
  21 ## Options
  22
  23 This rule accepts a single options argument with the following defaults:
  24
  25 ```json
  26 "space-infix-ops": ["error", { "int32Hint": false }]
  27 ```
  28
  29 ### `int32Hint`
  30
  31 Set the `int32Hint` option to `true` (default is `false`) to allow write `a|0` without space.
  32
  33 ```js
  34 var foo = bar|0; // `foo` is forced to be signed 32 bit integer
  35 ```
  36
  37 Examples of **incorrect** code for this rule:
  38
  39 ```js
  40 /*eslint space-infix-ops: "error"*/
  41 /*eslint-env es6*/
  42
  43 a+b
  44
  45 a+ b
  46
  47 a +b
  48
  49 a?b:c
  50
  51 const a={b:1};
  52
  53 var {a=0}=bar;
  54
  55 function foo(a=0) { }
  56 ```
  57
  58 Examples of **correct** code for this rule:
  59
  60 ```js
  61 /*eslint space-infix-ops: "error"*/
  62 /*eslint-env es6*/
  63
  64 a + b
  65
  66 a       + b
  67
  68 a ? b : c
  69
  70 const a = {b:1};
  71
  72 var {a = 0} = bar;
  73
  74 function foo(a = 0) { }
  75 ```
  76
  77 ## When Not To Use It
  78
  79 You can turn this rule off if you are not concerned with the consistency of spacing around infix operators.