On Friday, 24 July 2015 at 19:56:55 UTC, Shammah Chancellor wrote:
I put up a PR for phobos awhile ago for concepts as a library
to kind of start the discussion around concepts. There seemed
to be some interest around the PR, so I have rebased it and
fixed the formatting.
Please take a look:
https://github.com/D-Programming-Language/phobos/pull/2627
-Shammah
Doing it as a library would miss a lot of the point of concepts :
- Compiler can do a fair amount of semantic analysis on template
before instantiating them. This work is done once rather than
repeating it a every template instantiation.
- It allow for much more clearer error messages. Anyone having
to maintain some meta code will understand what I'm talking about
here.
- It make compile time and runtime polymorphism more alike. I do
think we'd all agree that Andrei approach to mention template
arguments as compile time arguments and go from there is a good
move. Concept would be the same move, but for typing. By reusing
common language constructs (C++ failed to use that opportunity)
for instance.
