lesson2

nodeJS/Learning/02/src/index.ts

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+let myName: string = "John Doe";
+let nothingMuch: undefined = undefined;
+
+//Array
+//let arrayName: type[] =[value1, value2];
+let myArray: number[] = [1, 2, 3]
+let happyArray: Array<number> = [1, 2, 3]
+
+//if change in the future, myArray = ...
+
+//Tuples
+//Special type of array that allows you to specify the type of each element in that array
+//let tupleName: [type1, type2, type3] = [value1, value2, value3]
+
+//Enums
+// Enums are a way to define a set of named constants
+// You only give me some options
+
+enum Color {
+    Red = "red",
+    Green = 2,
+    Blue = "blue",
+}
+
+let myColor = Color.Blue
+//ts can show options
+
+enum Direction {
+    up = 1,
+    down = 2,
+    left = 3,
+    right = 4,
+}
+
+let playerDirection: Direction = Direction.right
+
+// Type or Interface (can use interface instead of type), for objects
+// question mark, meaning optional and doesnt need to be there
+type character = {
+    name: string;
+    age: number;
+    optional?: boolean;
+}
+
+//unsure types
+//Any (normal javascript, can put anything)
+
+//Union type
+
+let myUnion: number | string = 123;
+myUnion = "Hello world";
+//myUnion = false; error cuz has to be number or string
+
+//Functions
+
+const addNumbers = (a: number, b: number, c:string): number => {
+    console.log(c);
+    let sum = a+b
+    return sum;
+}
+
+addNumbers(1,2, `We are adding these numbers ${1} and ${2}`)
+