Phobos2: sorting and std.typecons.Tuple

[Christopher Wright]

Andrei Alexandrescu wrote:
> bearophile wrote:
>> Andrei Alexandrescu:
>>> s/recursive/transitive/
>>> Litmus test: recursive could recurse forever. Transitive never does.
>>
>> I have used the word recursive because the functions I have designed 
>> (and I think they are designed correctly) call themselves until they 
>> stop calling themselves because a stopping criterion is met. That's 
>> recursivity, I think.
> 
> But then what if you have a web of class objects that ultimately will 
> close a cycle?
> 
> Transitive: you'd use a worklist. Recursive: you'd recurse forever.
> 
> 
> Andrei

bearophile explicitly said "structs". I assume it would extend to 
primitives, treating pointers as integer types. I also assume it would 
call .toHash on any object.

This would still allow you to recurse infinitely, but it would require 
added effort:
struct S
{
	C c;
}
class C
{
	S s;
	this () { s.c = this; }
	auto toHash () { return s.toHash; }
}