singleton pattern

The conventional singleton pattern is really something that is used to overcome the fact that all code must be in a class.

class Singleton {
private static instance: Singleton;
private constructor() {
// do something construct...
}
static getInstance() {
if (!Singleton.instance) {
Singleton.instance = new Singleton();
// ... any one time initialization goes here ...
}
return Singleton.instance;
}
someMethod() { }
}
let something = new Singleton() // Error: constructor of 'Singleton' is private.
let instance = Singleton.getInstance() // do something with the instance...

However, if you don't want lazy initialization you can instead just use a namespace:

namespace Singleton {
// ... any one time initialization goes here ...
export function someMethod() { }
}
// Usage
Singleton.someMethod();

Warning : Singleton is just a fancy name for global

For most projects namespace can additionally be replaced by a module.

// someFile.ts
// ... any one time initialization goes here ...
export function someMethod() { }
// Usage
import {someMethod} from "./someFile";