deleight/dist/cjs/function/context/context.js

A library with 9 modules for writing more expressive web applications with traditional HTML, CSS and JavaScript.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.setContext = void 0;
/**
 * Wraps a function to ensure that it does not start running if the value of
 * `running` in the provided lock is truthy. This is relevant for functions that
 * use promises such as network requests and for mutually exclusive long-running
 * operations which should not run at the same time.
 *
 * If the function returns a promise,
 * the promise will be awaited before the context will be reset to allow any
 * function using the lock to run again.
 *
 * The function will simply ignore calls before it is ready to run
 * again, returning `undefined`.
 *
 * Pending tests. Please report bugs.
 *
 * @example
 *
 *
 * @param fn
 * @returns
 */
function setContext(fn, context) {
    if (!context)
        context = { running: false };
    else if (context.running === undefined)
        context.running = false;
    return (...args) => {
        if (context.running)
            return;
        context.running = true;
        const result = fn(...args);
        if (result instanceof Promise) {
            result.then(() => context.running = false);
        }
        else
            context.running = false;
        return result;
    };
}
exports.setContext = setContext;