There was a [great article][1] about how react implements it's virtual DOM. There are some really interesting ideas in there but they are deeply buried in the implementation of the React framework.
However, it's possible to implement just the virtual DOM and diff algorithm on it's own as a set of independent modules.
just the bare necessities of state management.
Hotlink it from https://unpkg.com/valoo.
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I heard some points of criticism to how React deals with reactivity and it's focus on "purity". It's interesting because there are really two approaches evolving. There's a mutable + change tracking approach and there's an immutability + referential equality testing approach. It's difficult to mix and match them when you build new features on top. So that's why React has been pushing a bit harder on immutability lately to be able to build on top of it. Both have various tradeoffs but others are doing good research in other areas, so we've decided to focus on this direction and see where it leads us.
I did want to address a few points that I didn't see get enough consideration around the tradeoffs. So here's a small brain dump.
"Compiled output results in smaller apps" - E.g. Svelte apps start smaller but the compiler output is 3-4x larger per component than the equivalent VDOM approach. This is mostly due to the code that is usually shared in the VDOM "VM" needs to be inlined into each component. The tr
| export const h=(t,p,...c)=>({t,p,c,k:p&&p.key}) | |
| export const render=(e,d,t=d.t||(d.t={}),p,r,c,m,y)=> | |
| // arrays | |
| e.map?e.map((e,p)=>render(e,d,t.o&&t.o[p])): | |
| // components | |
| e.t.call?(e.i=render((render.c=e).t(Object.assign({children:e.c},e.p),e.s=t.s||{},t=> | |
| render(Object.assign(e.s,t)&&e,d,e)),t.i||d,t&&t.i||{}),d.t=t=e):( | |
| // create notes | |
| m=t.d||(e.t?document.createElement(e.t):new Text(e.p)), | |
| // diff props |
| // Tracking cursor position in real-time without JavaScript | |
| // Demo: https://twitter.com/davywtf/status/1124146339259002881 | |
| package main | |
| import ( | |
| "fmt" | |
| "net/http" | |
| "strings" | |
| ) |
| /* ----------------------------------------- * | |
| Lazy List Implementation | |
| * ----------------------------------------- */ | |
| // Haskell-like infinite List, implemented with es6 generators | |
| // Lazyness lets you do crazy stuff like | |
| List.range(0, Infinity) | |
| .drop(1000) | |
| .map(n => -n) |
