alt Hacker NewsGenerally, you don't. I'm not sure why the parent suggested you should normally do this. However, there are occasional specific situations in which it's helpful, and that's when you use it.
Generally, you don't. I'm not sure why the parent suggested you should normally do this. However, there are occasional specific situations in which it's helpful, and that's when you use it.
It just is an improvement for a bunch of reasons.
1. Consistency across the board (places where it's required for metaprogramming, lambdas, etc). And as a nicety it forces function/method names to be aligned instead of having variable character counts for the return type before the names. IMHO it makes skimming code easier.
2. It's required for certain metaprogramming situations and it makes other situations an order of magnitude nicer. Nowadays you can just say `auto foo()` but if you can constrain the type either in that trailing return or in a requires clause, it makes reading code a lot easier.
3. The big one for everyday users is that trailing return type includes a lot of extra name resolution in the scope. So for example if the function is a member function/method, the class scope is automatically included so that you can just write `auto Foo::Bar() -> Baz {}` instead of `Foo::Baz Foo::Bar() {}`.