ryanmorr

function port(fn) {
    return Function.prototype.bind.call(Function.call, fn);
}

// Usage:

// port the `forEach` method of the Array prototype
const each = port([].forEach);
// Use standalone by passing the contextual object as the first argument
each(document.querySelectorAll('div'), (el) => console.log(el));

ryanmorr

function isPlainObject(value) {
    if (!value || typeof value !== 'object') {
        return false;
    }
    const prototype = Object.getPrototypeOf(value);
    return prototype === null || prototype === Object.getPrototypeOf({});
}

// Usage:

ryanmorr

function scope(obj, callback) {
    const source = callback.toString();
    const vars = Object.getOwnPropertyNames(obj).map((key) => `${key} = this['${key}']`);
    const body = source.substring(source.indexOf('{') + 1, source.lastIndexOf('}'));
    const fn = new Function(`var ${vars.join(',')}; ${body}`);
    fn.call(obj);
}

// Usage:

ryanmorr

function updateAttribute(element, name, newVal, oldVal = null) {
    if (name[0] === 'o' && name[1] === 'n') {
        name = name.slice(2).toLowerCase();
        if (newVal) {
            element.addEventListener(name, newVal);
        }
        if (oldVal) {
            element.removeEventListener(name, oldVal);
        }
    } else if (newVal == null || newVal === false) {

ryanmorr

function callbackMiddlewareProxy(callback) {
    const middleware = [];
    const push = middleware.push.bind(middleware);
    return new Proxy(callback, {
        get: (target, prop) => {
            if (prop === 'use') {
                return push;
            }
            return target[prop];
        },

ryanmorr

function templit(tpl, tag) {
    let exec;
    return (data) => {
        if (!exec) {
            const vars = Object.getOwnPropertyNames(data).map((key) => `${key} = this['${key}']`);
            exec = tag == null
                ? new Function(`var ${vars.join(',')}; return \`${tpl}\``)
                : new Function('__tag', `var ${vars.join(',')}; return __tag\`${tpl}\``);
        }
        return tag == null ? exec.call(data) : exec.call(data, tag);

ryanmorr

const has = {}.hasOwnProperty;

function getPath(root, tester, path = []) {
    for (const key in root) {
        if (has.call(root, key)) {
            const value = root[key];
            if (tester(key, value) === true) {
                path.push(key);
                return path;
            }

ryanmorr

// https://stackoverflow.com/a/46759625

function isConstructable(fn) {
    try {
        Reflect.construct(function () {}, [], fn);
        return true;
    } catch (e) {
        return false;
    }
}

ryanmorr

// https://developer.mozilla.org/en-US/docs/Web/API/Navigator/sendBeacon#sending_analytics_at_the_end_of_a_session

const callbacks = [];

function unload(callback) {
    callbacks.push(callback);
};

document.addEventListener('visibilitychange', () => {
    if (document.visibilityState === 'hidden') {

ryanmorr

function *stateGenerator(state, reducer) {
    let action;
    while (true) {
        if (action) {
            state = reducer(state, action);
        }
        action = yield state;
    }
}