ts-lazy-proxy

A tiny TypeScript utility that provides a lazy-initialized, read/write proxy for constant-like objects.

• Package: package.json
• Source: src/index.ts
• Main API:
  • LazyConstProxy
  • LazyProxyHandler

Install

npm install ts-lazy-proxy

Quick example

import { LazyConstProxy } from 'ts-lazy-proxy';

function createHeavyObject() {
    console.log('creating heavy object');
    return {
        value: 42,
        increment() {
            this.value += 1;
        },
    };
}

const lazy = LazyConstProxy(createHeavyObject);

// The heavy object is created only when a property is accessed:
console.log(lazy.value); // -> logs "creating heavy object", then "42"
lazy.increment();
console.log(lazy.value); // -> "43"

Exemple with a class:

import { LazyConstProxy } from 'ts-lazy-proxy';

class HeavyClass {
    value: number;

    constructor() {
        console.log('HeavyClass instantiated');
        this.value = 100;
    }

    double() {
        this.value *= 2;
    }
}

const lazyInstance = LazyConstProxy(() => new HeavyClass());
console.log(lazyInstance.value); // -> logs "HeavyClass instantiated", then "100"
lazyInstance.double();
console.log(lazyInstance.value); // -> "200"

API is forwarded from the package entry (src/index.ts) and implemented in src/LazyConstProxy.ts. The handler type is declared in src/types.ts.

License

MIT — see package.json for