@propagate_inbounds getindex(A::AdjOrTransAbsMat, i::Int, j::Int) = wrapperop(A)(A.parent[j, i])
j need to be constrained to
Ints? They may in principle be anything that the parent array supports, and the wrapper should simply switch the order. Is this necessary for ambiguity resolution? In that case, custom arrays that accept non-int indices – are they expected to add methods to
Transpose and other such wrappers?