How can I test at compile time whether T is an instance of an interface ?

[H. S. Teoh]

Try this:

	interface I {}
	class C : I {}
	class D {}
	struct S {}

	pragma(msg, is(C : I));	// true
	pragma(msg, is(D : I));	// false
	pragma(msg, is(S : I));	// false

So probably what you want is something like this:

	void register(C, ARGS...)(ARGS args)
		if (behavesLikeFoo!C || is(C : IFoo))
		...


T

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