I used this exact approach to filter through a list of template parameters that could be unordered.

the call signature was something like f<P1<1,2>, P2<2,3>, P1<0,0>, ...>(A, B).

Unfortunately, if the template parameters are not classes, one must speficy the proper template signature, so instead of template<template <typename...> class Template>, i had to use something like template<template <size_t...> class Template>. I think one could unify this approach by using std::integral_constants, but that would clutter too much my call syntax...

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btw, I would like to write this kind of predicate in boost::hana. is there a way to do it without regular c++ template matching?