Elm

Help, my recursive Decoder caused a runtime exception!

The one runtime exception nearly every Elm developer will encounter sooner or later is this one, dealing with recursive JSON decoders:

Uncaught TypeError: Cannot read property ‘tag’ of…

Delayed HTTP requests in Elm, line-by-line

I figured it would be fun to take a tiny function and explain how it works line by line.

Elm reactor and custom HTML

elm-reactor is an underrated tool. Not only does it do on-demand recompilation of Elm source code, but it can serve up other assets, too.

But did you know you can serve your own HTML with live-compiled Elm code, too? This is useful if you need JS interop…

Demystifying Elm JSON Decoders

Coming from JavaScript, where JSON is the most natural thing ever, having to write decoders to work with…

5 Things you didn’t know about Elm

Or perhaps you did. Reminders can’t hurt, though.

1. Changing types in record update syntax

Record update syntax { a | b = c } is restricted in various ways: you cannot add or remove fields…

Optimising for performance in Elm, Pt. 5

Pitfalls you may run into

When optimising for performance, there are a few things to watch out for.

Micro-benchmarks and JIT compilers

Optimising for performance in Elm, Pt. 4

Optimising a toHex function

The other day, someone on the Elm-lang Slack asked for an (efficient) toHex : Int -> String implementation. Of course, efficiency shouldn’t be the primary concern when doing something…

Optimising for performance in Elm, Pt. 3

Optimising the rebalancing operation in a self-balancing binary search tree

One of the core requirements for a self-balancing binary search tree, is that it, well, self-balances…

Optimising for performance in Elm, Pt. 2

Optimising the foldl operation in a recursive data structure

Let’s start with a some code I plucked from an earlier implementation of an alternative Dict implementation.

Optimising for performance in Elm, Pt. 1

Part 1: Introduction

First, let’s get the obvious disclaimers out of the way.

The real problem is that programmers have spent far too much time worrying about efficiency in the wrong places and…