[kbenson]

In Perl, it's fairly idiomatic to use a postfix condition on a return like that when doing early return. Some of that is obviated by Rust being typed, some is not. e.g.

    sub compute_interest( $amount, $interest ) {
        return $amount if $interest == 0; # Quick return
        die "We don't allow computation of negative interest rates" if $interest < 0; # Throw an exception
    
        # Do the actual work
        ...
    }

Edit: Also, it's worth noting that Perl enforces some behavior on this by only allowing postfix conditionals to follow a single statement, not blocks, so it's not just a regular conditional with the order reversed.

[kazagistar]

I've always disliked this aspect of Perl... I prefer control flow to be obvious.

[AstralStorm]

Hiding the actual control part on the right is pretty bad, yes.

Other than that, early returns can simplify flow a lot - otherwise you may have to do massive nesting ifs or many flags. Or even goto or exceptions.

[kbenson]

It's less bad than it seems, since it's a common idiom in Perl, so you're used to looking at it. It can be quite bad if abused, but so can so much in Perl.

When used with a return or die (or my personal favorite for debugging with 'warn "FOO" if $ENV{DEBUG};"), the fact that flow is affected is obvious by the very first characters in the statement, so it's obvious to then look for when it applies.

Like so many features of languages, how it looks from the outside compared to how it looks from those that are well versed in the language can be quite different (not to say that everything that looks like a wart in Perl is okay once you get used to it, every language has real warts). That's another aspect to this whole thing, how much to you emphasize ergonomics that are primarily for learning and novices. Features focused at novices to the expense of those familiar with the language are interesting, because they may draw a lot of people to your language, but you may not retain them very well.