eslint/docs/rules/default-param-last.md

   1 # enforce default parameters to be last (default-param-last)
   2
   3 Putting default parameter at last allows function calls to omit optional tail arguments.
   4
   5 ```js
   6 // Correct: optional argument can be omitted
   7 function createUser(id, isAdmin = false) {}
   8 createUser("tabby")
   9
  10 // Incorrect: optional argument can **not** be omitted
  11 function createUser(isAdmin = false, id) {}
  12 createUser(undefined, "tabby")
  13 ```
  14
  15 ## Rule Details
  16
  17 This rule enforces default parameters to be the last of parameters.
  18
  19 Examples of **incorrect** code for this rule:
  20
  21 ```js
  22 /* eslint default-param-last: ["error"] */
  23
  24 function f(a = 0, b) {}
  25
  26 function f(a, b = 0, c) {}
  27 ```
  28
  29 Examples of **correct** code for this rule:
  30
  31 ```js
  32 /* eslint default-param-last: ["error"] */
  33
  34 function f(a, b = 0) {}
  35 ```