typescript+matchtypescriptmatch

match consumer examples

How a TypeScript app uses @danrabydev/match ^0.3.1: exhaustive Status.match, one ApiResult namespace, peek-then-match, merge, and diagnostics on Error. No _ hatch.

August 24, 2026

typescriptapp/src/status.ts

import { createMatchable, type MatchableOf } from "@danrabydev/match";

export const Status = createMatchable({
  Idle: () => ({}),
  Loading: (msg: string) => ({ msg }),
  Success: (data: number) => ({ data }),
  Error: (err: Error) => ({ err }),
});

export type Status = MatchableOf<typeof Status>;

export function label(status: Status): string {
  return Status.match(status, {
    Idle: () => "waiting",
    Loading: ({ msg }) => `state: ${msg}`,
    Success: ({ data }) => `got ${data}`,
    Error: ({ err }) => err.message,
  });
}

label(Status.Loading("fetching"));
// => "state: fetching"