dypsilon

async function addComment(comment) {
  const post = await fetchPostBySlug(comment.postSlug);

  if (!post.isCommentingEnabled) {
    throw new Error('Commenting is disabled.');
  }

  const isAllowed = await isUserAllowedToComment(post, comment.user);

  if (!isAllowed) {

dypsilon

function addComment(comment) {
  return fetchPostBySlug(comment.postSlug)
    .then((post) => {
      if (!post.isCommentingEnabled) {
        return Promise.reject(new Error('Commenting is disabled.'));
      }

      return isUserAllowedToComment(post, comment.user)
        .then((isAllowed) => ({ isAllowed, post }));
    }).then((input) => {

dypsilon

function addComment(comment) {
  return fetchPostBySlug(comment.postSlug).then((post) => {
    if (!post.isCommentingEnabled) {
      return Promise.reject(new Error('Commenting is disabled.'));
    }

    return isUserAllowedToComment(post, comment.user).then((isAllowed) => {
      if (!isAllowed) {
        return Promise.reject(
          new Error('The user is not allowed to comment on this post.')

dypsilon

function addComment(comment, done) {
  fetchPostBySlug(comment.postSlug, (err, post) => {
    if (err) return done(err);

    if (!post.isCommentingEnabled) {
      return done(new Error('Commenting is disabled.'));
    }

    isUserAllowedToComment(post, comment.user, (err, isAllowed) => {
      if (err) return done(err);

dypsilon

{
  "user": "58bb380d222c2239a2b16ae9",
  "postSlug": "is-learning-dangerous",
  "comment": "A little learning is a dangerous thing."
}

dypsilon

const {tagged} = require('daggy');

// const
const K = (a) => (b) => a;

// Reader Transformer
module.exports = (M) => {
  const ReaderT = tagged('run');

  ReaderT.lift = ReaderT.prototype.lift = (m) => ReaderT(K(m));

dypsilon

const {tagged} = require('daggy');

// const
const K = (a) => (b) => a;

// Reader Transformer
module.exports = (M) => {
    const ReaderT = tagged('run');

    ReaderT.lift = (m) => ReaderT(K(m));

dypsilon

/**
 * This short program will encrypt the user password
 * and insert a new record into a mock database.
 */
const Reader = require('fantasy-readers');
const Future = require('fluture');
const R = require('ramda');
const crypto = require('crypto');

// our mock database

dypsilon

/**
 * This short program will encrypt the user password
 * and insert a new record into a mock database.
 */
const Reader = require('fantasy-readers');
const R = require('ramda');
const crypto = require('crypto');

// our mock database
const database = [

dypsilon

const {tagged} = require('daggy');

let Continuation = tagged('x');

Continuation.prototype.of = Continuation.of = x => {
  return new Continuation((resolve) => resolve(x));
}

Continuation.prototype.chain = function(f) {
  return this.x(f);