let bar: void;
bar = 2;
I'm a bit confused, can you clarify this for me? I understand when we use void with LET.
However, in a scenario like this:
function test(message): void {
console.log(message);
}
test("hi");
we still get the output "hi". Why is that?
In defining a function, the last type specifies the type of value that it returns.
You might be wondering why this is necessary.
function test(msg: string): void {
console.log(msg);
}
This particular function doesn't return anything.
let myVar: void = test("hello!");
console.log(myVar);
When you try to assign a value to myVar, it will be undefined because the function has no return value. This concept is illustrated in this example from Typescript.
let unusable: void = undefined;
So what does "return" mean? It refers to the data that a function sends back after being executed. For example:
function idk(): string {
return "Hello World!";
}
When I call this function, it returns a string.
let myVar: string = idk();
console.log(myVar);
You can learn more about the concept of returning values in functions from this documentation on returning values by MDN.
I find myself a bit perplexed while attempting to comprehend
I'm not quite grasping it, could you please explain. I understand when we use void with LET - got it
however, if I am interpreting it correctly in my mind, the latter part of the query depicts void as the return type of a function (essentially nothing) whereas the former segment demonstrates a void variable, which in Typescript is restricted to only null or undefined as values.
The latter portion functions effectively because the function does not attempt to return anything. It does not acknowledge "void" as an argument. The type of message is untyped, hence essentially any object would be permissible.
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