https://felixfong227.tumblr.com/post/158583912898/async-code-the-block-way

file.text

This is a simple text file that contain useless information that we are not going to use it anyways lol

index.js

const fs = require('fs-promise');
const path = require('path');
const co = require('co');
co(function *(){
    const content = yield fs.readFile(path.join(`${__dirname}/file.txt`), 'utf-8');
    const uppercase = content.toUpperCase();
    yield fs.writeFile(path.join(`${__dirname}/uppercase.text`), uppercase);
});

package.json

{
  "dependencies": {
    "co": "^4.6.0",
    "fs-promise": "^2.0.2"
  }
}

uppercase.text

THIS IS A SIMPLE TEXT FILE THAT CONTAIN USELESS INFORMATION THAT WE ARE NOT GOING TO USE IT ANYWAYS LOL

yarn.lock

# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
# yarn lockfile v1


any-promise@^1.0.0, any-promise@^1.3.0:
  version "1.3.0"
  resolved "https://registry.yarnpkg.com/any-promise/-/any-promise-1.3.0.tgz#abc6afeedcea52e809cdc0376aed3ce39635d17f"

co@^4.6.0:
  version "4.6.0"
  resolved "https://registry.yarnpkg.com/co/-/co-4.6.0.tgz#6ea6bdf3d853ae54ccb8e47bfa0bf3f9031fb184"

fs-extra@^2.0.0:
  version "2.1.2"
  resolved "https://registry.yarnpkg.com/fs-extra/-/fs-extra-2.1.2.tgz#046c70163cef9aad46b0e4a7fa467fb22d71de35"
  dependencies:
    graceful-fs "^4.1.2"
    jsonfile "^2.1.0"

fs-promise@^2.0.2:
  version "2.0.2"
  resolved "https://registry.yarnpkg.com/fs-promise/-/fs-promise-2.0.2.tgz#cfea45c80f46480a3fd176213fa22abc8c159521"
  dependencies:
    any-promise "^1.3.0"
    fs-extra "^2.0.0"
    mz "^2.6.0"
    thenify-all "^1.6.0"

graceful-fs@^4.1.2, graceful-fs@^4.1.6:
  version "4.1.11"
  resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.11.tgz#0e8bdfe4d1ddb8854d64e04ea7c00e2a026e5658"

jsonfile@^2.1.0:
  version "2.4.0"
  resolved "https://registry.yarnpkg.com/jsonfile/-/jsonfile-2.4.0.tgz#3736a2b428b87bbda0cc83b53fa3d633a35c2ae8"
  optionalDependencies:
    graceful-fs "^4.1.6"

mz@^2.6.0:
  version "2.6.0"
  resolved "https://registry.yarnpkg.com/mz/-/mz-2.6.0.tgz#c8b8521d958df0a4f2768025db69c719ee4ef1ce"
  dependencies:
    any-promise "^1.0.0"
    object-assign "^4.0.1"
    thenify-all "^1.0.0"

object-assign@^4.0.1:
  version "4.1.1"
  resolved "https://registry.yarnpkg.com/object-assign/-/object-assign-4.1.1.tgz#2109adc7965887cfc05cbbd442cac8bfbb360863"

thenify-all@^1.0.0, thenify-all@^1.6.0:
  version "1.6.0"
  resolved "https://registry.yarnpkg.com/thenify-all/-/thenify-all-1.6.0.tgz#1a1918d402d8fc3f98fbf234db0bcc8cc10e9726"
  dependencies:
    thenify ">= 3.1.0 < 4"

"thenify@>= 3.1.0 < 4":
  version "3.2.1"
  resolved "https://registry.yarnpkg.com/thenify/-/thenify-3.2.1.tgz#251fd1c80aff6e5cf57cb179ab1fcb724269bd11"
  dependencies:
    any-promise "^1.0.0"