alien-signals
Project Status: Preview
The goal of alien-signals
is to create a Signal library with the lowest overhead.
We have set the following scheduling logic constraints:
- Based on Push-Pull
- No dynamic objects
- No use of Array/Set/Map
- No recursion calls
- Class properties must be fewer than 10 (https://v8.dev/blog/fast-properties)
Experimental results have shown that with these constraints, it is possible to achieve excellent performance for a Signal library without using sophisticated scheduling strategies. The overall performance of alien-signals
is approximately 400% that of Vue 3.4's reactivity system.
For more detailed performance comparisons, please visit: https://github.com/transitive-bullshit/js-reactivity-benchmark
Motivation
To achieve high-performance code generation in https://github.com/vuejs/language-tools, I needed to write some on-demand computed logic using Signals, but I couldn't find a low-cost Signal library that satisfied me.
In the past, I accumulated some knowledge of reactivity systems in https://github.com/vuejs/core/pull/5912, so I attempted to develop alien-signals
with the goal of creating a Signal library with minimal memory usage and excellent performance.
Since Vue 3.5 switched to a Pull reactivity system in https://github.com/vuejs/core/pull/10397, I continued to research the Push-Pull reactivity system here. It is worth mentioning that I was inspired by the doubly-linked concept, but alien-signals
does not use a similar implementation.
Usage
Basic
import { signal, computed, effect } from 'alien-signals';
const count = signal(1);
const doubleCount = computed(() => count.get() * 2);
effect(() => {
console.log(`Count is: ${count.get()}`);
});
console.log(doubleCount.get());
count.set(2);
console.log(doubleCount.get());
Effect Scope
import { signal, effectScope } from 'alien-signals';
const count = signal(1);
const scope = effectScope();
scope.run(() => {
effect(() => {
console.log(`Count in scope: ${count.get()}`);
});
count.set(2);
});
scope.stop();
count.set(3);
Roadmap
Version | Savings |
---|
0.1 | Satisfies use cases for Vue Vapor Mode |
0.0 | Satisfies use cases for vuejs/language-tools |