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node_modules/zwitch/readme.md

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+# zwitch
+
+[![Build][build-badge]][build]
+[![Coverage][coverage-badge]][coverage]
+[![Downloads][downloads-badge]][downloads]
+[![Size][size-badge]][size]
+
+Handle values based on a property.
+
+## Install
+
+[npm][]:
+
+```sh
+npm install zwitch
+```
+
+## Use
+
+```js
+var zwitch = require('zwitch')
+
+var handle = zwitch('type')
+
+handle.invalid = invalid
+handle.unknown = unknown
+handle.handlers.alpha = handle
+
+handle({type: 'alpha'})
+```
+
+Or, with a `switch` statement:
+
+```javascript
+function handle(value) {
+  var fn
+
+  if (!value || typeof value !== 'object' || !('type' in value)) {
+    fn = invalid
+  } else {
+    switch (value.type) {
+      case 'alpha':
+        fn = handle
+        break
+      default:
+        fn = unknown
+        break
+    }
+  }
+
+  return fn.apply(this, arguments)
+}
+
+handle({type: 'alpha'})
+```
+
+## API
+
+### `zwitch(key[, options])`
+
+Create a functional switch, based on a `key` (`string`).
+
+###### `options`
+
+Options can be omitted and added later to `one`.
+
+*   `handlers` (`Object.<Function>`, optional)
+    — Object mapping values to handle, stored on `one.handlers`
+*   `invalid` (`Function`, optional)
+    — Handle values without `key`, stored on `one.invalid`
+*   `unknown` (`Function`, optional)
+    — Handle values with an unhandled `key`, stored on `one.unknown`
+
+###### Returns
+
+`Function` — See [`one`][one].
+
+#### `one(value[, rest...])`
+
+Handle one value.  Based on the bound `key`, a respective handler will be
+invoked.
+If `value` is not an object, or doesn’t have a `key` property, the special
+“invalid” handler will be invoked.
+If `value` has an unknown `key`, the special “unknown” handler will be invoked.
+
+All arguments, and the context object, are passed through to the [handler][],
+and it’s result is returned.
+
+#### `one.handlers`
+
+Map of [handler][]s (`Object.<string, Function>`).
+
+#### `one.invalid`
+
+Special [`handler`][handler] invoked if a value doesn’t have a `key` property.
+If not set, `undefined` is returned for invalid values.
+
+#### `one.unknown`
+
+Special [`handler`][handler] invoked if a value does not have a matching
+handler.
+If not set, `undefined` is returned for unknown values.
+
+### `function handler(value[, rest...])`
+
+Handle one value.
+
+## Related
+
+*   [`mapz`](https://github.com/wooorm/mapz)
+    — Functional map
+
+## License
+
+[MIT][license] © [Titus Wormer][author]
+
+<!-- Definitions -->
+
+[build-badge]: https://img.shields.io/travis/wooorm/zwitch.svg
+
+[build]: https://travis-ci.org/wooorm/zwitch
+
+[coverage-badge]: https://img.shields.io/codecov/c/github/wooorm/zwitch.svg
+
+[coverage]: https://codecov.io/github/wooorm/zwitch
+
+[downloads-badge]: https://img.shields.io/npm/dm/zwitch.svg
+
+[downloads]: https://www.npmjs.com/package/zwitch
+
+[size-badge]: https://img.shields.io/bundlephobia/minzip/zwitch.svg
+
+[size]: https://bundlephobia.com/result?p=zwitch
+
+[npm]: https://docs.npmjs.com/cli/install
+
+[license]: license
+
+[author]: https://wooorm.com
+
+[one]: #onevalue-rest
+
+[handler]: #function-handlervalue-rest