Time

Turns the current time into a reactive value. It is useful for clocks, "updated just now" indicators, relative time displays, and any UI that should refresh itself based on time.

When to use

• When you need the current time as a reactive value.
• When the UI should refresh at a specific interval.
• When you want not only the raw date, but also a mapped value derived from it.

What it can do

• Provide the current date and time in milliseconds.
• Refresh the value with a given interval.
• Return either the raw date or the result of your custom mapping.

Constructor parameters

• updatePer — Update interval in milliseconds, or a function that returns it.
• map — Function that maps the current Date into a custom value.
• abortSignal — Stops internal reactions and timers when destroyed.

Public properties

• ms — Current timestamp in milliseconds.
• date — Current Date object.
• value — Current mapped value, or the raw date when no mapping is provided.

Public methods

• destroy() — Stops updates and cleans up the instance.

Usage example

import { createTime } from "mobx-swiss-knife";

const time = createTime({
  updatePer: 1000,
});

console.log(time.date);
console.log(time.ms);
console.log(time.value);

Example with a mapped value

import { createTime } from "mobx-swiss-knife";

const seconds = createTime({
  map: (date) => date.getSeconds(),
});

console.log(seconds.value);