Lazy variadic not working, any alternatives?

[John Colvin via Digitalmars-d-learn]

On Tuesday, 26 May 2015 at 06:04:59 UTC, Tofu Ninja wrote:
> On Tuesday, 26 May 2015 at 05:54:11 UTC, John Colvin wrote:
>> Something like this appears to work:
>>
>> import std.typetuple : allSatisfy;
>>
>> enum implicityConvertibleToBool(T) = is(T : bool);
>>
>> bool tok_and(Args...)(lazy Args terms)
>> if(allSatisfy!(implicitlyConvertibleToBool, Args))
>> {
>> 	auto backup = getInputLocation();
>> 	foreach(term; terms)
>> 	{
>> 		if(term == false)
>> 		{
>> 			rewind(backup);
>> 			return false;
>> 		}
>> 	}
>> 	return true;
>> }
>
> Hmmm.... this does seem to work. Does this essentially expand 
> out to tok_and(lazy bool arg1, lazy bool arg2, ...)?

Apparently yes, which surprised me. Storage classes and 
TypeTuples (or Arguments, as they are now) are a bit of a dark 
corner. E.g.

void foo(ref int, ref int);
alias A(T...) = T;
static assert(is(ParameterTypeTuple!foo == 
A!(ParameterTypeTuple!foo)));

That fails.