UserGalileo

// Let's just use the simplest monad, Identity
import { Identity } from 'wherever';

// These are our new elements
const f = x => Identity(x + 1);
const g = x => Identity(x + 2);
const h = x => Identity(x + 3);

UserGalileo

// These are our elements
const f = x => x + 1;
const g = x => x + 2;
const h = x => x + 3;

// This is our neutral element, a function which does nothing
const id = x => x;

// This is the composition
f(g(h(1))) // 7

UserGalileo

import { NgModule, ModuleWithProviders, InjectionToken, Inject, Injector } from '@angular/core';
import { CommonModule } from '@angular/common';

export const INSTANTIATED_SERVICES = new InjectionToken<any[]>('instantiated services');

/**
 * This module takes an array of services
 * and instantiates them for you. They'll be
 * singletons for the injector of the importing module.
 *

UserGalileo

/**
 * This interceptor ensures that the app makes requests
 * with relative paths correctly server-side.
 * Requests which start with a dot (ex. ./assets/...)
 * or relative ones ( ex. /assets/...) will be converted
 * to absolute paths
 */
import { Inject, Injectable, Injector, PLATFORM_ID } from '@angular/core';
import { isPlatformServer } from '@angular/common';
import { HttpEvent, HttpHandler, HttpInterceptor, HttpRequest } from '@angular/common/http';