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\n\nFunctional pattern matching with the full power of Typescript.\n
\n\n## Getting started\n\nTo install from npm:\n\n```\nnpm install @effect/match\n```\n\nOnce you have installed the library, you can import the necessary types and functions from the `@effect/match` module.\n\n```ts\nimport * as Match from \"@effect/match\"\n```\n\n## Defining a Matcher\n\nTo define a `Matcher` from a given type, you can use the `type` constructor function.\n\nYou can then use the `when`, `not` & `tag` combinators to specify the patterns to match against.\n\nFor example:\n\n```ts\nimport * as Match from \"@effect/match\"\nimport { pipe } from \"@effect/data/Function\"\n\nconst match = pipe(\n Match.type<{ a: number } | { b: string }>(),\n Match.when({ a: Match.number }, (_) => _.a),\n Match.when({ b: Match.string }, (_) => _.b),\n Match.exhaustive,\n)\n\nconsole.log(match({ a: 0 })) // 0\nconsole.log(match({ b: \"hello\" })) // \"hello\"\n```\n\nYou can also create a `Matcher` from a value using the `value` constructor function.\n\nFor example:\n\n```ts\nimport * as Match from \"@effect/match\"\nimport { pipe } from \"@effect/data/Function\"\n\nconst result = pipe(\n Match.value({ name: \"John\", age: 30 }),\n Match.when(\n { name: \"John\" },\n (user) => `${user.name} is ${user.age} years old`,\n ),\n Match.orElse(() => \"Oh, not John\"),\n)\n\nconsole.log(result) // \"John is 30 years old\"\n```\n\n## Types of patterns\n\n### Predicates\n\nValues can be tested against arbitrary functions.\n\n```ts\nimport * as Match from \"@effect/match\"\nimport { pipe } from \"@effect/data/Function\"\n\nconst match = pipe(\n Match.type<{ age: number }>(),\n Match.when({ age: (age) => age >= 5 }, (user) => `Age: ${user.age}`),\n Match.orElse((user) => `${user.age} is too young`),\n)\n\nconsole.log(match({ age: 5 })) // \"Age: 5\"\nconsole.log(match({ age: 4 })) // \"4 is too young\"\n```\n\n### `not` patterns\n\n`not` lets you match on everything but a specific value.\n\n```ts\nimport * as Match from \"@effect/match\"\nimport { pipe } from \"@effect/data/Function\"\n\nconst match = pipe(\n Match.type