I think I found another way (looking at the source): length(mytupletype.parameters)
Is this something I can rely on, or some internal API that may change? Also, would it make sense to define the whole abstract array interface for Tuple types, eg size(t::Type{Tuple}) = (length(t.parameters),) getindex(t::Type{Tuple}, index::Int) = t.parameters[index] etc in Base, or am I abusing Tuple types here? Best, Tamas On Wed, Mar 23 2016, Tamas Papp wrote: > Hi, > > How do I get the length of a tuple _type_? In other words, is there a > standard idiom for > > foo{N}(::Type{NTuple{N}}) = N > > Best, > > Tamas