eslint/docs/src/rules/max-statements-per-line.md

   1 ---
   2 title: max-statements-per-line
   3 layout: doc
   4 rule_type: layout
   5 related_rules:
   6 - max-depth
   7 - max-len
   8 - max-lines
   9 - max-lines-per-function
  10 - max-nested-callbacks
  11 - max-params
  12 - max-statements
  13 ---
  14
  15
  16 A line of code containing too many statements can be difficult to read. Code is generally read from the top down, especially when scanning, so limiting the number of statements allowed on a single line can be very beneficial for readability and maintainability.
  17
  18 ```js
  19 function foo () { var bar; if (condition) { bar = 1; } else { bar = 2; } return true; } // too many statements
  20 ```
  21
  22 ## Rule Details
  23
  24 This rule enforces a maximum number of statements allowed per line.
  25
  26 ## Options
  27
  28 ### max
  29
  30 The "max" object property is optional (default: 1).
  31
  32 Examples of **incorrect** code for this rule with the default `{ "max": 1 }` option:
  33
  34 ::: incorrect
  35
  36 ```js
  37 /*eslint max-statements-per-line: ["error", { "max": 1 }]*/
  38
  39 var bar; var baz;
  40 if (condition) { bar = 1; }
  41 for (var i = 0; i < length; ++i) { bar = 1; }
  42 switch (discriminant) { default: break; }
  43 function foo() { bar = 1; }
  44 var foo = function foo() { bar = 1; };
  45 (function foo() { bar = 1; })();
  46 ```
  47
  48 :::
  49
  50 Examples of **correct** code for this rule with the default `{ "max": 1 }` option:
  51
  52 ::: correct
  53
  54 ```js
  55 /*eslint max-statements-per-line: ["error", { "max": 1 }]*/
  56
  57 var bar, baz;
  58 if (condition) bar = 1;
  59 for (var i = 0; i < length; ++i);
  60 switch (discriminant) { default: }
  61 function foo() { }
  62 var foo = function foo() { };
  63 (function foo() { })();
  64 ```
  65
  66 :::
  67
  68 Examples of **incorrect** code for this rule with the `{ "max": 2 }` option:
  69
  70 ::: incorrect
  71
  72 ```js
  73 /*eslint max-statements-per-line: ["error", { "max": 2 }]*/
  74
  75 var bar; var baz; var qux;
  76 if (condition) { bar = 1; } else { baz = 2; }
  77 for (var i = 0; i < length; ++i) { bar = 1; baz = 2; }
  78 switch (discriminant) { case 'test': break; default: break; }
  79 function foo() { bar = 1; baz = 2; }
  80 var foo = function foo() { bar = 1; };
  81 (function foo() { bar = 1; baz = 2; })();
  82 ```
  83
  84 :::
  85
  86 Examples of **correct** code for this rule with the `{ "max": 2 }` option:
  87
  88 ::: correct
  89
  90 ```js
  91 /*eslint max-statements-per-line: ["error", { "max": 2 }]*/
  92
  93 var bar; var baz;
  94 if (condition) bar = 1; if (condition) baz = 2;
  95 for (var i = 0; i < length; ++i) { bar = 1; }
  96 switch (discriminant) { default: break; }
  97 function foo() { bar = 1; }
  98 var foo = function foo() { bar = 1; };
  99 (function foo() { var bar = 1; })();
 100 ```
 101
 102 :::
 103
 104 ## When Not To Use It
 105
 106 You can turn this rule off if you are not concerned with the number of statements on each line.