typescript function expects a type as an argument code example
Example 1: typescript default parameter
function sayName({ first, last = 'Smith' }: {first: string; last?: string }): void {
const name = first + ' ' + last;
console.log(name);
}
sayName({ first: 'Bob' });
Example 2: typescript annotate return type
function add(x: number, y: number): number {
return x + y;
}