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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
// @ts-check
/**
* TypeScript can't understand the lazyRequireGetter mechanism, due to how it defines
* properties as a getter. This function, instead provides lazy loading in a
* TypeScript-friendly manner. It applies the lazy load memoization to each property
* of the provided object.
*
* Example usage:
*
* const lazy = createLazyLoaders({
* moduleA: () => require("module/a"),
* moduleB: () => require("module/b"),
* });
*
* Later:
*
* const moduleA = lazy.moduleA();
* const { objectInModuleB } = lazy.moduleB();
*
* @template {{ [key: string]: any }} T
* @param {T} definition - An object where each property has a function that loads a module.
* @returns {T} - The load memoized version of T.
*/
export function createLazyLoaders(definition) {
/** @type {any} */
const result = {};
for (const [key, callback] of Object.entries(definition)) {
/** @type {any} */
let cache;
result[key] = () => {
if (cache === undefined) {
cache = callback();
}
return cache;
};
}
return result;
}