jmglov

(defproject clj-prod "0.1.0-SNAPSHOT"
  :description "Clojure in Production"
  :license {:name "MIT"
            :url "https://opensource.org/licenses/MIT"}
  :dependencies [[org.clojure/clojure "1.10.0"]
                 [amazonica "0.3.139"]
                 [cheshire "5.8.1"]])

jmglov

Clojure in Production - Lesson 1

Getting started

• Install JDK 8 or higher. OpenJDK or the Oracle JDK are both fine.
• Install the Clojure command line tools or Leiningen.

Our production system

Before we get started with any coding, let's be responsible engineers and do a little design. And before we get started with any design, let's be responsible engineers and ask our "product owner" (this document) what we're building.

jmglov

;; # Functional Programming with Clojure - L01

;; ## Why does Clojure have so many parens?

;; Most programming languages use infix notation for operators:

;; `1 + 2 + 3 + 4`

;; And put the name of the function before the parens grouping its arguments:

jmglov

(defmethod aero.core/reader 'skeys [_ _ {:keys [req opt req-un opt-un] :as key-defs}]
  (let [req (or req [])
        opt (or opt [])
        req-un (or req-un [])
        opt-un (or opt-un [])]
    (eval `(s/keys :req ~req
                   :opt ~opt
                   :req-un ~req-un
                   :opt-un ~opt-un))))

jmglov

;; -*- mode: emacs-lisp -*-
;; This file is loaded by Spacemacs at startup.
;; It must be stored in your home directory.

(defun dotspacemacs/layers ()
  "Configuration Layers declaration.
You should not put any user code in this function besides modifying the variable
values."
  (setq-default
   ;; Base distribution to use. This is a layer contained in the directory

jmglov

Mob Programming Dojo

Back to the Checkout kata

http://codekata.com/kata/kata09-back-to-the-checkout/

• One requirement at a time
• Must have a passing test
• Once the requirement is verified, a new requirement will be given

jmglov

'-?>'(X, Fs) ->
  reduce(
    fun({F, A},    Acc)                        -> apply(F, [Acc|A]);
       ({M, F, A}, Acc)                        -> apply(M, F, [Acc|A]);
       (F,         Acc) when is_function(F, 1) -> F(Acc)
    end, X, Fs).

jmglov

(ns spec-test-utils
  (:require [clojure.spec.test :as stest]
            [clojure.test :refer [is testing]]))

(defn- check [function num-tests]
  (if num-tests
    (stest/check function {:clojure.spec.test.check/opts {:num-tests num-tests}})
    (stest/check function)))

(defn checking

jmglov

;; Packages

(require 'package)
(add-to-list 'package-archives
             '("melpa-stable" . "http://stable.melpa.org/packages/") t)
(add-to-list 'package-archives
             '("melpa.org" . "http://melpa.org/packages/") t)
(add-to-list 'package-archives
             '("marmalade" . "http://marmalade-repo.org/packages/") t)

jmglov

(ns ping-pong-go
  (:require [clojure.core.async :as async :refer [<! >!]]))

(defn ping [ch]
  (println "Ping")
  (>! ch :ping)
  (<! (async/timeout 500)))

(defn pong [ch]
  (println "Pong")