jethrolarson

// Similar to Future but contains a series of future values
const {I, compose} = require('../util')

// ( -> a) -> Stream a
function _Stream(pusher) {
    this.push = pusher || I
    this['@@type'] = "Stream"
}

const Stream = pusher => new _Stream(pusher)

jethrolarson

var FT = require('myFunctionalTestFramework');
module.exports = FT.suite("Array", {
    "is a functor": (it)=> {
        var ar = [1]
        return it.all(
            it('returns array with value incremented').isLike([2], ar.map(x=>x+1))
            , it('returns new array').isnt(ar, ar.map(a => a))
        )
    }
})

jethrolarson

---
  extends: "eslint:recommended"
  root: true
  env:
    es6: true
    browser: true
    node: true
  ecmaFeatures:
    modules: false
  rules:

jethrolarson

We couldn’t find that file to show.

jethrolarson

// There's something elegant about this...
const foo = (bar, baz) => Object.assign({}, baz, {bar})

jethrolarson

Dependency Inversion Principle (DIP) is a design pattern popular in Object Oriented Programming but it's not alien to functional programming. Parameterizing dependencies is actually critical to maintaining functional purity--one of the most important aspects of FP.

While special dependency injection frameworks are sometimes used, a similar effect can be achieved using partial application.

jethrolarson

[alias]
    staged = diff --staged
    br = branch
    st = status
    co = checkout
    cod = checkout develop
    md = merge develop
    cb = checkout --track -b
    ci = commit
    ca = commit --amend

jethrolarson

const I = a => a

// this is just wrapping before and after functions around chai's BDD `it`
export const wrapIt = (before = I, after = I) => (label, fn) => {
    const ctx = before();
    it(label, (ctx) => fn.call(ctx));
    after(ctx);
};

jethrolarson

import React, {createClass} from 'react';

class MediaLibrary = createClass({
    foo() {
      this.setState({foo: !this.state.foo})
    },
    render() {
        return (<Bar onFoo={this.foo} />);
    }
}

jethrolarson

import {into, pipe, filter, map, propEq, prop} from 'ramda';

const doStuff = pipe(
  filter(propEq('status', 'active')),
  map(prop('age'))
);

// only iterates array once
into([], doStuff, [{status: 'active', name: 'Pam'}, {status: 'bad', name: 'Mancy'}]);
// ['Pam']