kritzcreek

Generating collections of random numbers in PureScript

A problem that I've seen beginners run into in Haskell or PureScript a couple of times now is how to generate a List of random numbers. It's a common requirement for little games (which make for great first projects) to generate these, and it definitely seems to be a stumbling block.

Why are random numbers hard?

Randomness is considered a side effect in purely functional languages, which means that to generate them you usually need access to Eff/IO, which in turn means we need to deal with Monads. And while generating a single random number is usually pretty easy with do-notation, the typical intuition beginners have built when going from single values to a collection is to use map, but that fails.

Type-Directed-Search to the rescue

justinwoo

Differences of Purescript from Elm

The syntax between Elm and Purescript are mostly the same, to the point where most Elm code can be converted to Purescript with copy-pasting and find-replace/multi-cursor editing.

Purpose of this document

Many people who have used Elm who are curious about/have tried/are using Purescript have asked me to put together a "differences from Elm" post to help them, and which I would also have found helpful.

Type Annotations

apmiller108

#!/bin/bash

set -e
set -o pipefail

CURRENT_OTP=$1
NEW_OTP=$2
CURRENT_NAME=""
NEW_NAME=""

groteck

port module Spelling exposing (..)

import Html exposing (..)
import Html.Events exposing (..)
import String


main =
    program
        { init = init

lencioni

// Usage:
// 
// function loader() {
//   return new Promise((resolve) => {
//     if (process.env.LAZY_LOAD) {
//       require.ensure([], (require) => {
//         resolve(require('./SomeComponent').default);
//       });
//     }
//   });

nuxodin

!(function(){
    var original = console;
    Object.defineProperty(window, 'console', {
        get:function(){
            return original;
        },
        set:function(value){
            original.log(value)
        }
    })

evancz

port module Spelling exposing (..)

import Html exposing (..)
import Html.App as App
import Html.Attributes exposing (..)
import Html.Events exposing (..)
import String


main =

chrisbuttery

import Html exposing (Html, text, div)
import Html.App as Html
import Mouse exposing (..)

main =
  Html.program
    { init = init
    , view = view
    , update = update
    , subscriptions = subscriptions

theoretick

#!/bin bash

function dammit_bundler() {
  bundle clean
  bundle install
}

function dammit_npm() {
  rm -fr ./node_modules/
  npm cache clean -f

Falconerd

/**
 * This gulpfile will copy static libraries and a index.html file as well as 
 * merge, babelify and uglify the rest of the javascript project.
 *
 * TODO:
 * - Separate media, libs and src with different watchers.
 * - Media and libs should only be copied to dist if they are different sizes.
 * 
 * The expected project is to be laid out as such:
 *