Hello all,=C2=A0

Just floating the idea= before composing the complete text. I recently blogged about a= hypothetical tuple slice functionality (and related design considerations)= and it seems useful & simple enough (conceptually and implementation w= ise) to be added in isolation to the Standard library (it may just have bee= n overlooked in previous versions, I couldn't find related proposals). = Long story short, given "tuple_slice" :=C2=A0

=C2=A0A= slice of=C2=A0

t=C2=A0can be o=
btained like so

Where=C2=A0[I1, I2)=C2=A0is the=C2=A0<= strong style=3D"box-sizing: border-box; font-family: inherit; font-style: i= nherit; outline: 0px; vertical-align: baseline;">exclusive range= =C2=A0of the subset

Proposed implementation below (please refer to the blog post = for more details):

= template = <std::size_t Ofst, class Tuple, std::size_t= .... I><= td id=3D"file-tuple_slice-cpp-LC4" class=3D"blob-code blob-code-inner js-fi= le-line" style=3D"box-sizing: border-box; font-style: inherit; outline: 0px= ; vertical-align: top; line-height: 20px; overflow: visible; position: rela= tive; word-wrap: normal; white-space: pre; background: transparent; padding= : 1px 10px !important;"> constexpr auto slice_impl(Tuple&& t, std::index_sequence<I...= >) <= td id=3D"file-tuple_slice-cpp-LC11" class=3D"blob-code blob-code-inner js-f= ile-line" style=3D"box-sizing: border-box; font-style: inherit; outline: 0p= x; vertical-align: top; line-height: 20px; overflow: visible; position: rel= ative; word-wrap: normal; white-space: pre; background: rgb(249, 249, 249);= padding: 1px 10px !important;">template= <std::size_t I1, std:= :size_t I2, classCont>constexpr = auto tuple_slice(Cont&& t) static_assert<= /span>(I2 >=3D I1, "= invalid slice");


	namespace detail {


	{
	return std::forward= _as_tuple(
	std::get<I + Ofst>(s= td::forward<Tuple>(t))...);
	}
	}



	{

	static_assert(std:= :tuple_size<std::decay_t<C= ont>>::value >=3D I2,
	"slice index out of bounds&q= uot;);

	return detai= l::slice_impl<I1>(std::forward<Cont>(t),
	std::make_index_sequence<I2 - I1>{});
	}=

Regards,=C2=A0

Nick





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