effect-pattern-matching

What problem does it solve?

This Skill helps you avoid brittle, non-exhaustive manual tag checks when working with discriminated unions, ADTs, Options, and schema unions in Effect v4 code.

Core Features & Use Cases

• Use Data.TaggedEnum pattern matching to get exhaustive, type-safe handling of tagged variants with $match and single-case guards with $is.
• Prefer Effect.match over Effect.result + manual checks to ensure both success and failure paths are handled declaratively.
• Handle common tagged structures correctly by using Option.match for Option types and Match.typeTags for Schema-based unions.

Use it when you are implementing state machines, domain events, command/result types, and conditional control flow that must remain correct as variants evolve.

Quick Start

Use the effect-pattern-matching skill to refactor your existing _tag/Result/Option branching into exhaustive $match handlers and type-safe $is guards.