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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Class numero quatro"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Some small remarks"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### Note on immutability"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "#'user/lst-2"
+      ]
+     },
+     "execution_count": 8,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(def lst [1 2 3 4 5 6 7 8])\n",
+    "\n",
+    "(defn times-2 [n]\n",
+    "    (* 2 n))\n",
+    "\n",
+    "(def lst-2 (map times-2 lst))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### Note on lazyness"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "(0 2 4 6 8 10 12 14 16 18)"
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(def all-numbers (range))\n",
+    "(def all-even-numbers (map times-2 all-numbers))\n",
+    "(take 10 all-even-numbers)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### Note on comments"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 36,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "(def foo 2) ;; this is a comment.  We call it a \"line comment\"\n",
+    "\n",
+    "(comment (println \"This is what we call a block comment, rarely used\"))\n",
+    "\n",
+    "\n",
+    "#_(println \"This is another type of block comment, more often used.  (used by david nolen)\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### Hyperfiddle\n",
+    "\n",
+    "This is the coolest thing ever!  http://www.hyperfiddle.net/"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### `if` and `when`\n",
+    "\n",
+    "Sometime, we only want to do \"stuff\" when something happen.  This is moment to use `if` and `when`"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "#'user/print-odd-or-even"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(defn print-odd-or-even [n]\n",
+    "    (if (odd? n)\n",
+    "        (println n \" is odd\")\n",
+    "        (println n \" is even\")))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Doing a web page!\n",
+    "\n",
+    "*  Intro html tags...\n",
+    "*  Let's do some html trash course\n",
+    "*  https://www.w3schools.com/TAGS/tryit.asp?filename=tryhtml_headers\n",
+    "*  https://www.w3schools.com/html/tryit.asp?filename=tryhtml_table_intro\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 32,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "(require '[clojupyter.misc.display :as display]) ;; https://github.com/clojupyter/clojupyter"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 38,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<h3>We can very easely print stuff from code</h3>"
+      ]
+     },
+     "execution_count": 38,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(display/html \"<h3>We can very easely print stuff from code</h3>\") "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 43,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "#'user/html-h1"
+      ]
+     },
+     "execution_count": 43,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(defn html-h1 [title])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "James Reeves made a fantastic, database, library for html called [hiccup](https://github.com/weavejester/hiccup)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<h3>hiccup is much better</h3>"
+      ]
+     },
+     "execution_count": 42,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(display/hiccup-html [:h3 \"hiccup is much better\"])"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 45,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "#'user/hiccup-h1"
+      ]
+     },
+     "execution_count": 45,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "(defn hiccup-h1 [title])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Dodgeball data"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "(def dodgeball-data\n",
+    "    [{:team-1 :drummonville :team-2 :montreal :points-1 4 :points-1 5}\n",
+    "     {:team-1 :drummonville :team-2 :montreal :points-1 4 :points-1 5}\n",
+    "     {:team-1 :drummonville :team-2 :montreal :points-1 4 :points-1 5}\n",
+    "     {:team-1 :drummonville :team-2 :montreal :points-1 4 :points-1 5}])\n",
+    "     \n",
+    "                        \n",
+    "                        "
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Lein-Clojure",
+   "language": "clojure",
+   "name": "lein-clojure"
+  },
+  "language_info": {
+   "file_extension": ".clj",
+   "mimetype": "text/x-clojure",
+   "name": "clojure",
+   "version": "1.9.0"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}