!z Native pattern matching for Javascript.


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- Install via npm: npm install z
- Require z in your code and use the matches function: const { matches } = require('z')

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- Matches by value: (x = 1) =>, (x = null) =>, (x = 'true') =>
- Matches by object or array: (x = {a: 1}) =>, (x = [1, 2]) =>
- Matches by type: (x = String) =>, (x = Boolean) =>
- Matches by instance: (x = Date) =>, (x = Person) =>
- Matches by splitting array into elements and tail (head, tail) => , (a, b, c, tail) =>, etc…

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- Example: Matches by Object property
``javascript
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!)
)

//output: Hey Maria, you are welcome!
`

- Example: Matches by type or instances
`javascript
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
`

- Example: matches Array content

> To match array content you need create multiple arguments for the match function, such as (a, b, c, tail) => {} , then each variable match each item from array. Note: last variable contains all remaining array items, formally named tail. Examples:
`javascript
const { matches } = require('z')

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

matches([1, 2])(
(a, tail) => 'a = 1, b = [2]'
)

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

- Example: Powerful recursive code which will remove sequential repeated items from Array.

> Can be mind blowing if it’s the first time you meet pattern matching, but you are gonna understand it!
`javascript
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]
``

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[Apache 2.0][apache-license]

[apache-license]:./LICENSE