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Seems to me that there is quite a bit of commentary on this subject, and you can find it by searching for its typical solution: guard clauses[1].

[1] http://wiki.c2.com/?GuardClause

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Yeah, Swift in particular really embraces that pattern.

Also functional languages with function guards e.g. while Erlang/Elixir does not have a return statement (and thus early return) you can write

    handle(Err, Results) when Err /= undefined ->
        handle_error(Err);
    handle(_, Results) ->
        % etc…
        .

though errors would generally be reified as the ad-hoc union of two tuples and would look more like this:

    handle({error, Info}) ->
        handle_error(Info);
    handle({ok, Results}) ->
        % handle results
        .

The functional style that you show certainly has multiple points where a value is returned, so you could call it "early return"; even if as a syntactic shorthand the keyword "return" is omitted. This is common across a lot of functional languages.

> The functional style that you show certainly has multiple points where a value is returned, so you could call it "early return";

It's not "early return" any more than:

    function(err, results) {
      if (!err) {
         // handle results
      } else {
         return handleError(err)
      }
    }

Right, though I was thinking of other examples of functional match style and returning a value. As seen in in Haskell, F# Rust etc.

e.g. https://doc.rust-lang.org/book/second-edition/ch06-02-match....

So value_in_cents can return a value of 1, 5, 10 or 25.

Saying that it "does not have a return statement" might be truish - but the fact that the "return" keyword is not needed to return values is just syntax.

Saying that there's no early return / multiple exit points is not so much. To my eye there are 4 places where that function can return a value. And the cases might not be simple numbers making the whole thing an expression, later examples on that page show how the cases can differ in side-effects.

Copy of the article, which doesn't require JS:

https://gist.github.com/jwilk/6e7ecb94b623a82d01cdcd9765f05b...

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