Minor problems with templates and mixins

[Oskar Linde]

Tom S skrev:
> While D's template system is really excellent, it's still got minor 
> problems. One is related to the current way to define function 
> templates. The other is about mixins - they seem to have a really 
> awkward nature.
> 
> * The two issues I present are by no means showstoppers, but rather 
> language details that make it unpleasant to use in a few cases.
> 
> 
> 1. Can't overload functions inside templates, e.g. the following code 
> won't work
> 
> # template foo(T) {
> #     T foo(int  a) { return T.init; }
> #     T foo(char a) { return T.init; }
> # }
> #
> # void main() {
> #     foo!(float)(1);
> # }
> 
> Yeah, the spec mentions that to be able to write foo!(float) instead of 
> foo!(float).foo, the template must have exactly one symbol in it, yet 
> it's not very comfortable to work with.

I posted about this a while ago too. For this case, the following 
workaround seems to work:

template foo_(T) {
   T foo(int  a) { return T.init; }
   T foo(char a) { return T.init; }
}

template foo(T) {
   alias foo_!(T).foo foo;
}

void main() {
   foo!(float)('a');
}

> It's possible to partially work around this limitation, e.g.

[snip]

> But this idea breaks when the function template is meant to be a 
> non-static member of some class.

The template-typedef(alias) workaround seems to work as a non-static 
member too.

Regards,

Oskar