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Markdown Cheatsheet

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lodash v4.17.20

`Array`

_.chunk
_.compact
_.concat

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

state-machine-component

A tiny (265 byte) utility to create state machine components using two pure functions.

🔥 JSFiddle Demo

Usage

The API is a single function that accepts 2 pure functions as arguments:

	//
	// Creates a new e-mail forwarder for your DomainFactory (www.df.eu) account
	//
	// Sadly DomainFactory doesn't provide an API for managing "ManagedHosting"
	// accounts, so I decided to write a short script for creating e-mail
	// forwarders, because I like to have one e-mail address for every service
	// I register for and I don't like to waste my time clicking through several
	// pages to archive this ;)
	//
	// To run this code you need PhantomJS - http://www.phantomjs.org/ (1.0.0)