add implementation

Author: Miha Zgubic

src/differentials/composite.jl

@@ -180,6 +180,10 @@ canonicalize(comp::Composite{<:Tuple, <:Tuple}) = comp
 # Dict composite are always in their canonical form.
 canonicalize(comp::Composite{<:Any, <:AbstractDict}) = comp
 
+# Composites of abstract primal types
+canonicalize(comp::Composite{Any, <:NamedTuple{L}}) where {L} = comp
+canonicalize(comp::Composite{Any, <:Tuple{L}}) where {L} = comp
+
 """
     _zeroed_backing(P)