@suchipi/tracker

Standalone Reactive tracker, like Meteor's Tracker.

Less than 1KiB gzipped.

Installation

npm install --save @suchipi/tracker

Sample usage

import { autorun, ReactiveVar } from "@suchipi/tracker";

const points = new ReactiveVar(0);

autorun(() => {
  // Because this function calls `points.get`, it will automatically be
  // re-run whenever `points.set` is called.
  console.log(`Score: ${points.get()}`);
});

points.set(1); // Logs "Score: 1"
points.set(45); // Logs "Score: 45"
points.set(0); // Logs "Score: 0"

API

autorun

Runs its received function now, and also registers it to be re-run in the future if any Dependency objects accessed during the function run get changed.

import { autorun } from "@suchipi/tracker";

Tracker.autorun(() => {
  // your code that uses Dependency objects goes here
});

Dependency

Used to represent a value or resource that can be changed. When it changes, any functions that accessed it during a Tracker.autorun call will be automatically re-run.

import { Dependency } from "@suchipi/tracker";

const dep = new Dependency();

// When something is reading from the value/resource, call:
dep.depend();

// When something has updated the value/resource, call:
dep.changed();

ReactiveVar

An object that holds a current value and creates a Dependency to track it. When the value is changed, the Dependency's changed method is called.

import { ReactiveVar } from "@suchipi/tracker";

const myVar = new ReactiveVar<number>(42);

myVar.get(); // 42
myVar.set(45);
myVar.get(); // 45