singleton-proxy/dist/esm/index.js

A lightweight TypeScript singleton implementation using Proxy pattern

export function singleton(target) {
    let instance = null;
    return new Proxy(target, {
        construct(target, args) {
            if (!instance) {
                instance = new target(...args);
            }
            return instance;
        },
        apply(target, thisArg, args) {
            if (!instance) {
                instance = target.apply(thisArg, args);
            }
            return instance !== null && instance !== void 0 ? instance : target.apply(thisArg, args);
        }
    });
}