Add some notes, sample code

.gitignore

@@ -53,3 +53,4 @@ google-services.json
 freeline.py
 freeline/
 freeline_project_description.json
+META-INF

.vscode/settings.json

@@ -1,3 +1,6 @@
 {
-  "code-runner.defaultLanguage": "kotlin"
+  "code-runner.defaultLanguage": "kotlin",
+  "editor.fontFamily": "Input Mono",
+  "editor.detectIndentation": false,
+  "code-runner.enableAppInsights": false
 }

README.md

@@ -1,5 +1,24 @@
-# learning-kotlin
+# General
+
+- A function that returns nothing is implicitly returning the `Unit` type
+- A function that never returns at all is implicitly returning the `Nothing` type (e.g. the `TODO()` function)
+
+# Terminology
+
+### Single-Expression Functions
+
+Function's that only evaluate a single expression can have their return type, curly braces, and return statement removed.
 
 ```kotlin
-val x = 9
+// Verbose
+fun sayHello(name: String) {
+  println("Hello, $name")
+}
+
+// Single-expression function
+fun sayHello(name: String) = println("Hello, $name")
 ```
+
+# Tidbits
+
+File-level functions in Kotlin are represented in Kotlin as static methods on a class with a name based on the file in which they are declared.

SimVillage.kt

@@ -0,0 +1,13 @@
+/**
+ * Chapter 5 - Anaonymous Functions & the Function Type
+ * SimVillage
+ */
+
+fun main(args: Array<String>) {
+  print("HI!")
+
+  println({
+    val currentYear = 2020
+    "Welcome to SimVillage, Mayor! ©$currentYear"
+  }())
+}