A series of function calls that each do something and each returns a value.
> Okay, here's an easier question. What will happen here, and why?
A function call that does something and returns a value, because in this language complex types are passed by reference.
Doesn't make it functional
> A function call that does something and returns a value,
Ah, so you don't know.
Here's what will actually happen:
TypeError: Can only call Document.getElementById on instances of Document
If it was functional this would never be the case. But since this is 90s-era OOP, you have to do this:
const function_reference = document.getElementById.bind(document);
function_reference("#id");This is not what functional programming is. Functional programming is a completely different paradigm for writing code, and it _is_ declarative by definition. The Wikipedia definition is pretty decent:
Functional programming is a programming paradigm where programs are constructed by applying and composing functions. It is a declarative programming paradigm in which function definitions are trees of expressions that map values to other values, rather than a sequence of imperative statements which update the running state of the program.
[1]: https://en.wikipedia.org/wiki/Functional_programming#Compari...
Functional programming uses stateless, immutable transformations to contorl data flow. The second you instantiate an object with some internal properties that change in memory, you are no longer programming functionally