On Sunday, 9 July 2017 at 19:30:25 UTC, Meta wrote:
I thought some more about the ramifications of having a Bottom
type in D. Having a special type like this interacts badly with
most aspects of D's generic programming capabilities, even on
the simplest level. At the least we would probably have to
create special cases everywhere in the compiler and/or
libraries that check if the type we're working with is the
bottom type. A few simple cases I can think of off the top of
my head:
alias Bottom = typeof(assert(0)); //for convenience
Bottom* pb; //Must be statically disallowed as this makes no
sense
Bottom[] ab; //ditto
cast(Bottom)1; //ditto
Another case that we should probably just statically disallow:
alias ImmutableBottom = immutable Bottom; //Ditto for shared,
const, etc.
This obviously doesn't make any sense anyway.
