Add idiomatic notebook

worldline · Oct 25, 2024 · 5c4ebe5 · 5c4ebe5
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diff --git a/material/conferences/2024-11-12-paris-jug/.gitignore b/material/conferences/2024-11-12-paris-jug/.gitignore
@@ -0,0 +1,2 @@
+.idea/
+out/
diff --git a/material/conferences/2024-11-12-paris-jug/idiomatic-01.ipynb b/material/conferences/2024-11-12-paris-jug/idiomatic-01.ipynb
@@ -0,0 +1,236 @@
+{
+ "cells": [
+  {
+   "metadata": {},
+   "cell_type": "markdown",
+   "source": [
+    "# Idiomatic Kotlin @ Paris JUG\n",
+    "Date: 2024 / 10 / 12"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "metadata": {
+    "collapsed": true,
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:33:51.646533Z",
+     "start_time": "2024-10-25T14:33:51.606114Z"
+    }
+   },
+   "source": [
+    "val event = \"Paris JUG\"\n",
+    "println(\"Hello $event\") // String template"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Hello Paris JUG\r\n"
+     ]
+    }
+   ],
+   "execution_count": 17
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:33:51.733128900Z",
+     "start_time": "2024-10-25T14:33:51.666925500Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "// Extension function: add a function to a class without inhetitance\n",
+    "fun String.randomCase(): String {\n",
+    "    // If expression\n",
+    "    return if (Math.random() > 0.5) uppercase() else lowercase()\n",
+    "}\n",
+    "println(event.randomCase())"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "PARIS JUG\r\n"
+     ]
+    }
+   ],
+   "execution_count": 18
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:33:51.861854200Z",
+     "start_time": "2024-10-25T14:33:51.755062200Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "// Default values for arguments\n",
+    "fun String.randomCaseChance(chance: Double = 0.5, offset: Int = 0) =\n",
+    "    // Single-expression functions with = (return type is inferred)\n",
+    "    (if (Math.random() > chance) uppercase() else lowercase()).drop(offset)\n",
+    "// Argument labels\n",
+    "println(event.randomCaseChance(offset = 3))\n",
+    "println(event.randomCaseChance(\n",
+    "    chance = 0.9,\n",
+    "    offset = 2,\n",
+    "    )\n",
+    ")"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "is jug\r\n",
+      "ris jug\r\n"
+     ]
+    }
+   ],
+   "execution_count": 19
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:33:52.069576Z",
+     "start_time": "2024-10-25T14:33:51.987387600Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "// Functions are 1st class citizen\n",
+    "fun String.transformToInt(transformer: (String) -> Int) = transformer(this)\n",
+    "// Parenthesis can be omitted for last lambda\n",
+    "// \"it\" is implicit for single-argument lambdas\n",
+    "// return is optionnal (in majot cases)\n",
+    "val count = event.transformToInt { it.length }\n",
+    "println(count)"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "9\r\n"
+     ]
+    }
+   ],
+   "execution_count": 20
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:33:52.233616600Z",
+     "start_time": "2024-10-25T14:33:52.158182800Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "typealias ST = String.() -> String\n",
+    "fun String.transformToString(transformer: ST) = transformer(this)\n",
+    "// String.() -> String means that the lambda has access to the string as this\n",
+    "// Allows to define DSL\n",
+    "val uppercased = event.transformToString { uppercase() }\n",
+    "print(\"Uppercased: $event\")"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Uppercased: Paris JUG"
+     ]
+    }
+   ],
+   "execution_count": 21
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:40:24.001881Z",
+     "start_time": "2024-10-25T14:40:23.881908900Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "// Filter, map, reduce out of the box (no need to convert to stream)\n",
+    "println(\n",
+    "    event.map { if (Math.random() > 0.5) it.uppercaseChar() else it.lowercaseChar() }.joinToString()\n",
+    ")\n",
+    "// More operators available\n",
+    "println(\n",
+    "    event.zip(\"2024\") { left, right -> \"$left/$right\" }\n",
+    ")"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "P, a, r, I, S,  , J, u, g\r\n",
+      "[P/2, a/0, r/2, i/4]\r\n"
+     ]
+    }
+   ],
+   "execution_count": 24
+  },
+  {
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2024-10-25T14:50:19.815828200Z",
+     "start_time": "2024-10-25T14:50:19.702384500Z"
+    }
+   },
+   "cell_type": "code",
+   "source": [
+    "// ? Means that the argument can be null\n",
+    "fun getUppercaseName(dev: Map<String, String>?): String {\n",
+    "    if (dev == null){\n",
+    "        return \"NONE\"\n",
+    "    }\n",
+    "    // Here dev is casted to Map<String, String>\n",
+    "    // ?: is the elvis operator\n",
+    "    return (dev[\"name\"] ?: \"NONE\").uppercase()\n",
+    "}\n",
+    "fun getUppercaseNameSe(dev: Map<String, String>?) = dev?.get(\"name\")?.uppercase() ?: \"NONE\"\n",
+    "val dev = mapOf(\"name\" to \"Yassine\", \"Meetup\" to \"ParisJug\")\n",
+    "println(dev)\n",
+    "println(getUppercaseName(dev))\n",
+    "println(getUppercaseNameSe(dev))"
+   ],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "{name=Yassine, Meetup=ParisJug}\r\n",
+      "YASSINE\r\n",
+      "YASSINE\r\n"
+     ]
+    }
+   ],
+   "execution_count": 27
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Kotlin",
+   "language": "kotlin",
+   "name": "kotlin"
+  },
+  "language_info": {
+   "name": "kotlin",
+   "version": "1.9.23",
+   "mimetype": "text/x-kotlin",
+   "file_extension": ".kt",
+   "pygments_lexer": "kotlin",
+   "codemirror_mode": "text/x-kotlin",
+   "nbconvert_exporter": ""
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}