I'm torn … do you extract the `return` even if som...

# codereview

[hho]

I'm torn … do you extract the return even if some branches don't return anything? I think I might like the version with multiple return statements better in this case…

return if (someExpr) {
  doSomeStuff()
  someThing
} else if (otherExpr) {
  doOtherStuff()
  otherThing
} else {
  throw RuntimeException("uh oh")
}

[Joffrey]

I extract those branches into functions with proper names that return a value, and then lift the return out of the if when I have one-liners in every branch. I would also likely make it a when because I think they look better as expressions than if when the whole if doesn't fit on a single line (especially if there are more than 2 branches)

[Joffrey]

Then extract the when expression into its own function so there is not even one return anymore

[Joffrey]

In short, your snippet in its context (which we don't have here) will likely look like:

return theWhenStuff()

With the following extra declarations:

fun theWhenStuff() = when {
    someExpr -> doSomeStuffThatReturnsSomeThing()
    otherExpr -> doSomeOtherStuffThatReturnOtherThing()
    else -> error("uh oh")
}

fun doSomeStuffThatReturnsSomeThing() {
    doSomeStuff()
    return someThing
}

fun doSomeOtherStuffThatReturnOtherThing() {
    doOtherStuff()
    return otherThing
}

[Joffrey]

even if some branches don't return anything

So your problem is with the throw there? That doesn't bother me. Throw returns Nothing which makes the whole thing clean IMO

[hho]

I really should make more (smaller) methods 🤦‍♂️
Thank you, that pushed me on the right track!

[Joffrey]

I'm sorry I initially missed the actual point of the question. But I guess it becomes kinda moot once you extract more functions.
I imagine you don't really have a problem with calling functions that can either throw or return something (basically all functions are like that), so I'd say having an expression that mixes values and failure doesn't really bother me either, in the same way.

The most obvious example of it would be:

val x = something ?: throw SomeException("blah")
// or
return something ?: throw SomeException("blah")

Although I have to admit this last part itches a tiny little bit. It would depend on context I guess

[Jon Senchyna]

I like the shift from if to when there. With the way the two are naturally indented, the when statement does a much better job of visually associating all of the branches back to the return.