auto auto function template in DLang

Question

From https://dlang.org/library/std/typecons/nullable.html:

auto auto nullable(T) (
  T t
);

What is this "double auto"?

Answer 1

It's a bug in the Ddox documentation generator. You can use Ddoc: https://dlang.org/phobos/std_typecons

Ddoc (DMD's built-in documentation generator) was there in the beginning and is the older system. Ddox was intended to be a replacement and thus both version are online, so that Ddox could be battle-tested. However, it still has a few issues which is why it hasn't replaced DMD's built-in documentation generator so far.