eslint/docs/src/rules/no-ex-assign.md

   1 ---
   2 title: no-ex-assign
   3 rule_type: problem
   4 further_reading:
   5 - https://bocoup.com/blog/the-catch-with-try-catch
   6 ---
   7
   8
   9
  10 If a `catch` clause in a `try` statement accidentally (or purposely) assigns another value to the exception parameter, it is impossible to refer to the error from that point on.
  11 Since there is no `arguments` object to offer alternative access to this data, assignment of the parameter is absolutely destructive.
  12
  13 ## Rule Details
  14
  15 This rule disallows reassigning exceptions in `catch` clauses.
  16
  17 Examples of **incorrect** code for this rule:
  18
  19 ::: incorrect
  20
  21 ```js
  22 /*eslint no-ex-assign: "error"*/
  23
  24 try {
  25     // code
  26 } catch (e) {
  27     e = 10;
  28 }
  29 ```
  30
  31 :::
  32
  33 Examples of **correct** code for this rule:
  34
  35 ::: correct
  36
  37 ```js
  38 /*eslint no-ex-assign: "error"*/
  39
  40 try {
  41     // code
  42 } catch (e) {
  43     var foo = 10;
  44 }
  45 ```
  46
  47 :::