pipey/README.md

Utility functions to convert class-based api's to parameter-based functions

# Pipey
Utility functions to convert instance methods's to context-free functions ready for use with [esnext pipeline operator](https://github.com/tc39/proposal-pipeline-operator) and point-free functional programming.

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[Read the documentation for more information](https://github.com/phenax/pipey/tree/master/docs)

## Install

#### To add the project to your project
```bash
yarn add pipey
```

## Usage

#### Import it to your file
```js
import { createPipe, createPipes, fromClassPrototype, compose } from 'pipey';
// Note: compose is a regular lodash-like compose function
```

#### fromClassPrototype
```js
const { map, filter } = fromClassPrototype(Array);

const doubleNumbers = map(x => x * 2);
const doubleOddNumbers = compose(doubleNumbers, filter(x => x % 2));

doubleOddNumbers([ 2, 3, 4, 5 ]); // Returns [ 6, 10 ]
```

#### createPipe
```js
const forEach = createPipe('forEach');
forEach(x => console.log(x))([ 1, 2, 3, 4 ]); // Logs 1 2 3 4
```

#### createPipes
```js
const { map, filter, split } = createPipes(['map', 'filter', 'split']);
const head = ([ first ]) => first;
const compact = filter(Boolean);

const getFirstNames = names =>
    names
        |> compact
        |> map(split(' '))
        |> map(head);

getFirstNames([ '', null, 'Akshay Nair', 'John Doe', 'Bruce Fucking Lee' ]); // Returns ['Akshay', 'John', 'Bruce']
```

### Example use cases

* Using with the amazing pipe operator
```js
const { map, filter, reduce } = fromClassPrototype(Array);

const fromPairs = reduce((acc, [ k, v ]) => ({ ...acc, [k]: v }), {});

const getInputData = () =>
    [...document.querySelectorAll('.js-input')]
        |> map($input => [ $input.name, $input.value ])
        |> filter(([_, value]) => value)
        |> fromPairs;

getInputData(); // Returns something like { email: 'han.solo@gmail.com', name: 'Han Solo' }
```

* Working with collection methods
```js
// Two ways to extract methods out (createPipes & fromClassPrototype)
const { map, filter } = fromClassPrototype(Array);
const { split } = createPipes(['split']);
const head = ([ first ]) => first;

const getFirstNames = compose(
    map(head),
    map(split(' ')),
    filter(Boolean),
);

getFirstNames([ '', null, 'Akshay Nair', 'John Doe', 'Bruce Fucking Lee' ]); // Returns ['Akshay', 'John', 'Bruce']
```


* Working with dom methods
```js
const { forEach, join } = fromClassPrototype(Array);
const { setAttribute } = fromClassPrototype(HTMLInputElement);
const inputs = ['.js-input-name', '.js-input-email'];

inputs
    |> join(', ')
    |> (selector => document.querySelectorAll(selector))
    |> forEach(setAttribute('disabled', 'disabled'));
```