On Monday, 30 March 2015 at 18:33:17 UTC, Andrei Alexandrescu
wrote:
On 3/30/15 8:04 AM, Steven Schveighoffer wrote:
On 3/29/15 1:34 PM, IgorStepanov wrote:
1. We should reject types which use opDispatch and alias this
at the
same time.
Why? Alias this has no filter. opDispatch can use template
constraints.
It makes perfect sense to prefer opDispatch, unless it doesn't
have a
valid match, and then use alias this instead.
For example, if I wanted to wrap a type so I can instrument
calls to
'foo', I could do something like this:
struct FooWrapper(T)
{
T t;
alias t this;
auto opDispatch(string s, A...)(A args) if(s == "foo") {
writeln("calling foo"); return t.foo(args); }
}
Why is this a bad use case?
The idea is to start restrictive and define interaction
meaningfully later based on compelling use cases. -- Andrei
Andrei, do you approve those changes? Can we move to work on my
github PR?
