Fixing ambiguity for Identity transform

Author: theogf

src/transform/transform.jl

@@ -17,6 +17,7 @@ struct IdentityTransform <: Transform end
 
 (t::IdentityTransform)(x) = x
 Base.map(::IdentityTransform, x::AbstractVector) = x
+_map(::IdentityTransform, x::AbstractVector) = x
 
 ### TODO Maybe defining adjoints could help but so far it's not working