Re: C++ Metaclasses proposal

2017-06-27 Thread Nicholas Wilson via Digitalmars-d

On Tuesday, 27 June 2017 at 15:57:01 UTC, Enamex wrote:
PDF: 
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0707r0.pdf
Reddit: 
https://www.reddit.com/r/programming/comments/6js4uv/metaclasses_in_c/


I thought a bit on possible patterns in D to accomplish the 
same without string mixins.


For example, defining the prototype `Foo_` then mixing in 
`mixin MyMetaclass!Foo_ Foo`.


Got stuck trying to 'forward' (or copy the implementation of) 
functions in `Foo_` into `Foo` after modifying them, though.


Besides trying to do it in D (please try still!), what do you 
think of the idea? In general and say versus a robust macro 
system with some level of access to CTFE? Or even just a good 
macro system (someone began discussing this on the reddit 
thread; talking about Racket macros).


Quite a lot of it seems doable with mixin templates and UDA 
reflection.

Ethan Watson's dconf talk is a good point of comparison.


C++ Metaclasses proposal

2017-06-27 Thread Enamex via Digitalmars-d
PDF: 
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0707r0.pdf
Reddit: 
https://www.reddit.com/r/programming/comments/6js4uv/metaclasses_in_c/


I thought a bit on possible patterns in D to accomplish the same 
without string mixins.


For example, defining the prototype `Foo_` then mixing in `mixin 
MyMetaclass!Foo_ Foo`.


Got stuck trying to 'forward' (or copy the implementation of) 
functions in `Foo_` into `Foo` after modifying them, though.


Besides trying to do it in D (please try still!), what do you 
think of the idea? In general and say versus a robust macro 
system with some level of access to CTFE? Or even just a good 
macro system (someone began discussing this on the reddit thread; 
talking about Racket macros).