globalStore

The createGlobalStore() function lets you create a global store (singleton) shared across the entire process. It is useful for storing a mutable value accessible from any module without passing it as a parameter.

WARNING

The store is global and mutable: avoid turning it into a “state manager”. Do not share values between requests if your runtime is long-lived (HTTP server), unless explicitly intended.

Interactive example

Typing: declare your stores

The store name (storeName) is typed via the GlobalStore interface. To add your keys and their types, use declaration merging:

declare module "@duplojs/utils" {
	interface GlobalStore {
		myStore: number;
	}
}

Syntax

interface GlobalStoreHandler<
	GenericValue extends unknown
> {
	readonly value: GenericValue;
	set(value: GenericValue): void;
}

function createGlobalStore<
	GenericStoreName extends keyof GlobalStore
>(
	storeName: GenericStoreName,
	defaultValue: GlobalStore[GenericStoreName]
): GlobalStoreHandler<GlobalStore[GenericStoreName]>;

Parameters

• storeName : Typed store name (key of GlobalStore).
• defaultValue : Value used only if the store does not exist yet.

Return value

A handler with:

• value : the current value.
• set(value) : updates the global value.