@AndrejMitrovic I don't know that the old alias syntax will be deprecated. At least, currently new alias syntax does not cover all of old syntax features.

1. New alias syntax cannot declare function type directly
    `alias int func(int);` is OK, but `alias fun = int(int);` is not valid.
2. New alias syntax cannot declare function pointer or delegate type with `extern`.
    `alias extern(C) int function() FP;` is OK, but `alias FP = extern(C) int function();` is not accepted.