typescript function

1interface Safer_Easy_Fix {
2    title: string;
3    callback: () => void;
4}
5interface Alternate_Syntax_4_Safer_Easy_Fix {
6    title: string;
7    callback(): void;
8}
9

1// Parameter type annotation
2function greet(name: string): string {
3 return name.toUpperCase();
4}
5
6console.log(greet("hello"));		// HELLO
7console.log(greet(1));				// error, name is typed (string)

1// define your parameter's type inside the parenthesis
2// define your return type after the parenthesis
3
4function sayHello(name: string): string  {
5  console.log(`Hello, ${name}`!);
6}
7
8sayHello('Bob'); // Hello, Bob!

1interface Easy_Fix_Solution {
2    title: string;
3    callback: Function;
4}
5

1// Named function
2
3//function with type as number
4function add(x: number, y: number): number {
5  // return sum of numbers entered as params
6  return x + y;
7}
8
9// Anonymous function
10
11// variable to call and define function
12let myAdd = function (x: number, y: number): number {
13  // return sum of numbers entered as params
14  return x + y;
15};

1// Named function
2function add(x: number, y: number): number {
3  return x + y;
4}
5
6// Anonymous function
7let myAdd = function (x: number, y: number): number {
8  return x + y;
9};