Functions
Functions in TypeScript can have typed parameters and return values.
In the following example, the function add receives two numbers and returns a number.
The function defines the types of the parameters and its return value using the : operator.
function add(a: number, b: number): number {
return a + b;
}
Arrow functions
Functions can also be defined as variables using the "arrow function" notation:
const add = (a: number, b: number): number => {
return a + b;
}
Arrow functions in TypeScript differ from regular functions when used in objects - they do not
manipulate the this value and use the same scope as the parent function. However - this trait
should not conern you if you are not using objects in TypeScript.
Arrow functions also support a shorter form - if the function is an expression and not a code block denoted using curly braces, it will return that expression as the output of the function.
For example:
const add = (a: number, b: number): number => a + b;
Exercise
Create a function named multiply that takes two number parameters and returns their product.
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