Elm view
- 1. How much view could a view-chuck chuck if a view-chuck could chuck view? Performance of Elm vs Other by Jesse Tomchak
- 2. Little about me Started into Elm about a year ago Just finished a teaching sabbatical at Woz-u Lots of JavaScript, interested in system languages like Rust, and anything else with great tooling
- 3. Performance Alert! The last measurement after something is done ...but the real benefit is that this approach leads to code that is easier to understand and maintain NO NO NO
- 4. Just one! Your own. (With a little help from your smart phone)
- 5. Blazing Fast HTML Part 1 - 2014 Part 2 - 2016 Part 3 - ??
- 6. Part 1 Who’s the new guy
- 7. 2 Points ➔ Purity means that the todoList function will always have the same output given the same input. So if we know state.tasks is the same, we can skip todoListentirely. ➔ Immutability makes it cheap to figure out when things are “the same”. Immutability guarantees that if two things are referentially equal, they must be structurally equal.
- 8. Part 2 Bit more pragmatic
- 9. 2 Points ➔ Skip Work The best way to speed up virtual DOM diffing is to skip it! So the programmer can say “only diff the view if the relevant model changed” with lazy, shouldComponentUpdate, or OnPush respectively. ➔ Align Work When you are adding and removing child nodes, a virtual DOM implementation can end up doing tons of pointless diffing. To avoid this you have Html.Keyed, key, or trackBy respectively.
- 11. So Let’s see it already Story for illustration purposes only
- 12. Take aways Elm is fast! Safe in types gets you there. It’s not a race, but Elm would win
- 13. Thank you! @jstoelm @jtomchak elm-slack : jtomchak JavaScript to Elm