@adrienlcp/result

A success-or-failure value in thirty lines, with no exceptions and no nulls. Zero dependencies.

import { Result } from '@adrienlcp/result'

const parse = (input: string): Result<number, 'not_a_number'> => {
  const value = Number(input)
  return Number.isNaN(value) ? Result.failure('not_a_number') : Result.success(value)
}

const result = parse(raw)
if (result.status === 'failure') return result.error // 'not_a_number'
result.data // number

Result<T = void, E = 'unknown'>. A result carrying nothing is Result.success() — no data key at all, so a caller cannot read undefined off something the signature never promised. Result.failure() with no argument means the unknown error.

pnpm add @adrienlcp/result