Finish Functions

Functions.playground/Contents.swift

@@ -0,0 +1,62 @@
+import Foundation
+
+func noArgumentAndNoReturnValue() {
+    "I don't know what I'm doing"
+}
+
+noArgumentAndNoReturnValue()
+
+func plusTwo(value: Int) {
+    let newValue = value + 2
+}
+
+plusTwo(value: 30)
+
+func newPlusTwo(value: Int) -> Int {
+    return value + 2
+}
+
+newPlusTwo(value: 30)
+
+func customAdd(value1: Int, value2: Int) -> Int {
+    value1 + value2
+}
+
+let customAdded = customAdd(value1: 10, value2: 30)
+
+// function(external internal: Type) -> Type
+func customMinus(_ lhs: Int, _ rhs: Int) -> Int {
+    lhs - rhs
+}
+
+customMinus(10, 2)
+
+customAdd(value1: 20, value2: 60)
+
+@discardableResult
+func myCustomAdd(_ lhs: Int, _ rhs: Int) -> Int {
+    lhs + rhs
+}
+
+func doSomethingComplicated(with value: Int) -> Int{
+    func mainLogic(value: Int) -> Int {
+        value + 2
+    }
+    
+    return mainLogic(value: value + 3)
+}
+
+doSomethingComplicated(with: 10)
+
+func getFullName(
+    firstName: String = "Foo",
+    lastName: String = "Bar"
+) -> String {
+    "\(firstName) \(lastName)"
+}
+
+getFullName()
+getFullName(firstName: "Gary")
+getFullName(lastName: "Gan")
+getFullName(firstName: "Gary", lastName: "Gan")
+

Functions.playground/contents.xcplayground

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<playground version='7.0' target-platform='macos' swift-version='6' buildActiveScheme='true' executeOnSourceChanges='true' importAppTypes='true'/>

swift-playground.xcworkspace/contents.xcworkspacedata

@@ -1,6 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Workspace
    version = "1.0">
+   <FileRef
+      location = "group:Functions.playground">
+   </FileRef>
    <FileRef
       location = "group:Variables.playground">
    </FileRef>