#massaman

Functional programming utilities for TypeScript. Rust's match and Result in TypeScript, layered over es-toolkit and ts-pattern.

npm install massaman

import { match, P, attempt, isOk } from 'massaman'

const result = attempt(() => JSON.parse(input))

const message = match(result)
  .with({ ok: true }, ({ value }) => `parsed ${typeof value}`)
  .with({ ok: false }, ({ error }) => `failed: ${error.message}`)
  .exhaustive()

#Where to start

• Introduction — what's bundled, what's original
• Installation & usage — install, imports, tree-shaking
• Philosophy — the FP stance, why no classes / no throws / no switch
• Concepts — short guides on the core ideas:
  • Result & Errors
  • Pattern matching
  • Composition
• Reference — every export, by area:
  • array · object · function · math · string · promise · error
  • predicate · control · conversion · match