jsdoc /* * @pattern /https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#()?&//=]*)/ */

• Matches by Object property ```js const { matches } = require('z')

const person = { name: 'Maria' } matches(person)( (x = { name: 'John' }) => console.log('John you are not welcome!'), (x) => console.log(Hey ${x.name}, you are welcome!) ) - Matches by type or instancesjs const { matches } = require('z')

const result = matches(1)( (x = 2) => 'number 2 is the best!!!', (x = Number) => number ${x} is not that good, (x = Date) => 'blaa.. dates are awful!' )

console.log(result) // output: number 1 is not that good - Matches Array contentjs const { matches } = require('z')

matches([1, 2, 3, 4, 5])( (a, b, c, tail) => 'a = 1, b = 2, c = 3, tail = [4, 5]'<br /> )

matches([1, 2])( (a, tail) => 'a = 1, tail = [2]'<br /> )

matches([1])( (a, b, tail) => 'Will not match here', (a = 2, tail = []) => 'Will not match here', (a = 1, tail) => 'Will match here, tail = []' ) ```

• Powerful recursive code which will remove sequential repeated items from Array ```js const { matches } = require('z')

const compress = (numbers) => { return matches(numbers)( (x, y, xs) => x === y ? compress([x].concat(xs)) : [x].concat(compress([y].concat(xs))), (x, xs) => x // stopping condition ) }

compress([1, 1, 2, 3, 4, 4, 4]) //output: [1, 2, 3, 4] ```

js match (res) { if (isEmpty(res)) { … } when ({ pages, data }) if (pages > 1) { … } when ({ pages, data }) if (pages === 1) { … } else { … } }

js match (arithmeticStr) { when (/(?<left>\d+) \+ (?<right>\d+)/) as ({ groups: { left, right } }) { process(left, right); } when (/(?<left>\d+) \+ (?<right>\d+)/) { process(left, right); } // maybe? else { ... } }

```js class Name { static Symbol.matcher { const pieces = matchable.split(' '); if (pieces.length === 2) { return { matched: true, value: pieces }; } } }

match ('Tab Atkins-Bittner') { when (^Name with [first, last]) if (last.includes('-')) { … } when (^Name with [first, last]) { … } else { ... } } ```

js const res = await fetch(jsonService) match (res) { when ({ status: 200, headers: { 'Content-Length': s } }) { console.log(`size is ${s}`); } when ({ status: 404 }) { console.log('JSON not found'); } when ({ status }) if (status >= 400) { throw new RequestError(res); } };

```js function todoApp(state = initialState, action) { return match (action) { when ({ type: 'set-visibility-filter', payload: visFilter }) { ({ ...state, visFilter }); } when ({ type: 'add-todo', payload: text }) { ({ ...state, todos: [...state.todos, { text, completed: false }] }); } when ({ type: 'toggle-todo', payload: index }) { const newTodos = state.todos.map((todo, i) => { return i !== index ? todo : { ...todo, completed: !todo.completed }; });

  ({
    ...state,
    todos: newTodos,
  });
}
else { state } // ignore unknown actions

} } ```

jsx <Fetch url={API_URL}> {props => match (props) { when ({ loading }) { <Loading />; } when ({ error }) { <Error error={error} />; } when ({ data }) { <Page data={data} />; } }} </Fetch>