On Saturday, 27 October 2012 at 11:41:07 UTC, bearophile wrote:
Peter Alexander:
void foo(ForwardRange Range)(Range r)
{
r.popBack();
}
And *immediately* get a type error without having to
instantiate it with a variety of different range types.
It's not an easy problem. To solve it the Rust language uses
typeclasses adapted from Haskell. But unlike the usual Haskell
compilers Rust doesn't use global type inferencing and it keeps
the C++-style monomorphization, so at run-time its generic
programming is as efficient as C++ generic programming.
Yeah, it's certainly not going to be easy. It's unfortunate that
D adopted the whole C++ style "glorified macros" approach to
templates -- it makes it very difficult to reason about (or
automate reasoning about) the semantics of your code.
Retrofitting some sort of structure to templates will be a
Herculean task, but I think it has to happen. It is clear to me
that the development process we use now (write the template, try
a few instantiations, pray) is unsustainable beyond simple
templates.
