Дмитрий Беляев

class Pizza {
    constructor() {
        this.crust = prompt('Choose your crust: ');
        this.toppingsCount = +prompt('How many toppings do you want?') || 0;
        this.toppings = [];
    }

    makeToppings() {
        const {toppings, toppingsCount} = this;
        for(let i = toppingsCount; i--;) {
            toppings.push(prompt('Choose your topping: '));
        }
    }

    makePizza() {
        const {crust, toppings} = this;
        return `Your order is done! You choose ${crust} crust with these toppings: ${toppings.length ? toppings.join(', ') : 'nothing'}`;
    }
}

let personalPizza = new Pizza();
personalPizza.makeTopping();
console.log(personalPizza.makePizza());

import chain from '@bingo347/fn/mappers/chain';
import extractField from '@bingo347/fn/mappers/extractField';

// создаем функцию для безопасного извлечения
const getBCDE = chain(
  extractField('B'),
  extractField('C'),
  extractField('D'),
  extractField('E')
);

// извлекаем
const ABCDE = getBCDE(A);

const TestClass = (function() {
    class TestClass {
        constructor() {
            this.calls = '';
        }

        toString() {
            return this.calls;
        }
    }

    Object.setPrototypeOf(TestClass.prototype, Function.prototype);

    function callTestClassInstance(el) {
        this.calls += String(el);
    }

    return new Proxy(TestClass, {
        construct(TestClass, args) {
            const instance = new TestClass(...args);
            const target = args => callTestClassInstance.apply(instance, args);
            Object.setPrototypeOf(target, TestClass.prototype);
            return new Proxy(target, {
                apply(target, _, args) {
                    return target(args);
                },
                get(_, name) {
                    return instance[name];
                },
                set(_, name, value) {
                    instance[name] = value;
                    return true;
                },
                has(_, name) {
                    return name in instance;
                },
                deleteProperty(_, name) {
                    return delete instance[name];
                },
                defineProperty(_, name, descriptor) {
                    return Object.defineProperty(instance, name, descriptor);
                },
                getOwnPropertyDescriptor(_, name) {
                    return Object.getOwnPropertyDescriptor(instance, name);
                },
                ownKeys() {
                    return Object.getOwnPropertyNames(instance).concat(Object.getOwnPropertySymbols(instance));
                }
            });
        }
    });
})();

const appleDevice     = /iP(hone|od|ad)/;
const applePhone      = /iPhone/i;
const appleIPod       = /iPod/i;
const appleTablet     = /iPad/i;
const androidPhone    = /(?=.*\bAndroid\b)(?=.*\bMobile\b)/i;
const androidTablet   = /Android/i;
const windowsPhone    = /Windows Phone/i;
const windowsTablet   = /(?=.*\bWindows\b)(?=.*\bARM\b)/i;
const otherBlackberry = /BlackBerry/i;
const otherOpera      = /Opera Mini/i;
const otherFirefox    = /(?=.*\bFirefox\b)(?=.*\bMobile\b)/i;
const sevenInch       = /(?:Nexus 7|BNTV250|Kindle Fire|Silk|GT-P1000)/i;

function match(regex, target = navigator.userAgent) {
    return regex.test(target);
}

export const isAppleDevice = match(applePhone) || match(appleIPod) || match(appleTablet) || match(appleDevice, navigator.platform);
export const isAndroidDevice = match(androidPhone) || match(androidTablet);
export const isWindowsDevice = match(windowsPhone) || match(windowsTablet);
export const isOtherDevice = match(otherBlackberry) || match(otherOpera) || match(otherFirefox);
export const isSevenInch = match(sevenInch);
export const isMobileDevice = isAppleDevice || isAndroidDevice || isWindowsDevice || isOtherDevice || isSevenInch;
export const isEmulator = isMobileDevice && !isWindowsDevice && (match(/Mac/, navigator.platform) || match(/Win32/, navigator.platform));