Possible enhancement: Concise return statements

[Timon Gehr]

On 08/15/2011 11:15 PM, Andrew Wiley wrote:
> On Mon, Aug 15, 2011 at 1:57 PM, Andrei Alexandrescu
> <SeeWebsiteForEmail at erdani.org <mailto:SeeWebsiteForEmail at erdani.org>>
> wrote:
>
>     On 8/15/11 2:19 PM, Jacob Carlborg wrote:
>
>         On 2011-08-15 21:00, Walter Bright wrote:
>
>             On 8/15/2011 3:54 AM, Timon Gehr wrote:
>
>                 'When the last ExpressionStatement in a function body is
>                 missing the
>                 ';', it is
>                 implicitly returned.'
>
>
>             This has been proposed several times before, it was also
>             proposed for
>             C++0x. The difficulty is it makes having a ; or not
>             substantially alter
>             the semantics. The history of these languages is that the
>             presence or
>             absence of ; can be hard to spot, as in:
>
>             for (int i = 0; i < 10; i++);
>             ... do this ...
>
>             which has cost at least one expert developer I know an
>             entire afternoon
>             staring at it convinced there was a compiler bug because his
>             loop
>             executed only once.
>
>             (And this is why D disallows this syntax.)
>
>
>         Can't we always automatically return the last expression, even if it
>         ends with a semicolon?
>
>
>     Then two semicolons mean return void :o).
>
>
> If you want void, you have to use this as your last expression:
> ...- --- .. -..;
>

Two semicolons means the last statement is an empty statement, so 
Andrei's suggestion would be sensible if the last expression was 
implicitly returned all the time ;)

@Topic:
So, I'm not convinced that accidents related to writing one surplus ; or 
leaving one ; away would lead to hard to find and impossible to 
statically catch bugs. (After all, such accidents would *always* make it 
into the type signature of the function.) As this apparently has been 
discussed before, does anyone actually have a real world example where 
it could be shown to be problematic?