ts-pattern 5.3.1

v5.3.1

on Node.js NPM

The main thing

You can know pattern match on symbol keys

Symbols used to be ignored in object patterns. They are now taken into account:

const symbolA = Symbol('symbol-a');
const symbolB = Symbol('symbol-b');

const obj = { [symbolA]: { [symbolB]: 'foo' } };
    
if (isMatching({ [symbolA]: { [symbolB]: 'foo' } }, obj)) {
   //  👆 used to return false, now returns true!
}

.exhaustive now throws a custom error

Several people have expressed the need to differentiate runtime errors that .exhaustive() might throw if your input value has an incorrect type and the problem couldn't be caught at compile time.

It's now possible with err instanceof NonExhaustiveError:

import { match, P, NonExhaustiveError }  from 'ts-pattern';

const fn = (input: string | number) => {
  return match(input)
    .with(P.string, () => "string!")
    .with(P.number, () => "number!")
    .exhaustive()
}

try {
  fn(null as string) // 👈 💥 
} catch (e) {
  if (e instanceof NonExhaustiveError) {
    // The input was invalid
  } else {
    // something else happened
  }
}

What's Changed

• build(deps-dev): bump braces from 3.0.2 to 3.0.3 in /examples/gif-fetcher by @dependabot in #262
• feat: throw custom ExhaustiveError when no matched pattern by @adamhamlin in #270
• Symbols as keys by @Ayc0 in #272

New Contributors

• @adamhamlin made their first contribution in #270
• @Ayc0 made their first contribution in #272

Full Changelog: v5.2.0...v5.3.1