On Wednesday, 19 July 2017 at 01:52:30 UTC, Walter Bright wrote:
I know how noreturn attributes work - I implemented them
decades ago in DMC and DMC++. They are supported by the DMD
optimizer and back end.
But they are a hack to the type system, and I suggest an
unnecessary one.
It describe the behaviour of the function: I think it is neither
necessary nor a good idea to express it as a type. assert(0) is
already accepted as a valid return statement of any type.
The backends for DMD, LDC and GDC would not be affected at all
by the addition of a bottom type to the front end, and it would
be trivial for the glue code to add the noreturn attribute for
functions that return the bottom type.
Said glue would be unnecessary with an attribute *that already
exists*.
