05fad0fcd6957848df5f1dbc5e136d0ba39c61f5
The matcher is now two three-overload factories; library.md documents why the union merge, inferred universe, conditional RequireKeys and cases-first paths were rejected, and lists the two open issues (the fallback sees all of T; a redundant _ is still accepted). testing.md records the language server as the autocomplete oracle, and CONTRIBUTING points the exception at the matcher's own test file. The backlog marks the design-doc and autocomplete groundwork done alongside the adoption.
tiny-pattern-ts
Pattern matching for TypeScript/ESM environments (F#-style, not regex).
Description
tiny-pattern-ts brings F#-style pattern matching to TypeScript. Patterns are
ordinary objects whose matches method is a TypeScript type guard, so narrowing
composes the way any other guard does. It is deliberately not a regex engine and
not a macro: there is no transpiler and no DSL to learn, and the type-level
contract is the feature — see development/library.md
for the design decisions and the known limitations.
Requirements
- Node.js >= 26 (
enginesfield; pinned via.node-version). - TypeScript >= 5.0 to consume the published declarations. The emitted
.d.tsuseconsttype parameters (TS 5.0) and keep their relative.tsspecifiers; both resolve on TS >= 5.0 innode10/node16/nodenext/bundler. - The package is ESM-only (no CommonJS shim).
API
Yet to be implemented
License
MIT © 2025 tmu. See LICENSE.
Contributing
Contributions are documented in CONTRIBUTING.md; the reasons behind the project's decisions, rejected alternatives, and known issues live in development/. AI coding agents start at AGENTS.md.