https://github.com/buschtoens/unsupported-value-error

Utility Error class for performing exhaustiveness checks via exceptions in TypeScript.
https://github.com/buschtoens/unsupported-value-error

control-flow exhaustiveness-checking types typescript

Last synced: 6 months ago
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Utility Error class for performing exhaustiveness checks via exceptions in TypeScript.

• Host: GitHub
• URL: https://github.com/buschtoens/unsupported-value-error
• Owner: buschtoens
• License: isc
• Created: 2020-04-07T10:51:21.000Z (about 6 years ago)
• Default Branch: master
• Last Pushed: 2023-12-15T02:26:11.000Z (over 2 years ago)
• Last Synced: 2024-10-09T12:43:07.728Z (over 1 year ago)
• Topics: control-flow, exhaustiveness-checking, types, typescript
• Language: TypeScript
• Size: 79.1 KB
• Stars: 0
• Watchers: 3
• Forks: 0
• Open Issues: 12
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

          
# unsupported-value-error

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Little TypeScript utility Error class for performing exhaustiveness checks via

exceptions, based on [this post by Dr. Axel Rauschmayer][blog-post].

[blog-post]: https://2ality.com/2020/02/typescript-exhaustiveness-checks-via-exceptions.html

```ts

enum NoYes {

  No = 'no',

  Yes = 'yes'

}

function toGerman(x: NoYes) {

  switch (x) {

    case NoYes.No: return 'Nein';

    // case NoYes.Yes: return 'Ja';

    default: throw new UnsupportedValueError(x);

    // => TS2345: Static TS error: Argument of type 'NoYes.Yes' is not assignable to parameter of type 'never'.

    // => Runtime: Unsupported value: 'yes'

  }

}

```