view is not supported

[CarloLucibello]

on julia 0.7:

julia> using AutoGrad
julia> view(rand(2,2,3),2,2,1:2)
2-element view(::Array{Float64,3}, 2, 2, 1:2) with eltype Float64:
 0.26936877599285936
 0.5965847464427165 

julia> view(Rec(rand(2,2,3)),2,2,1:2)
ERROR: MethodError: no method matching view(::Rec{Array{Float64,3}}, ::Int64, ::Int64, ::UnitRange{Int64})
Closest candidates are:
  view(::AbstractArray, ::Any...) where N at subarray.jl:132
Stacktrace:
 [1] top-level scope at none:0

Once view is supported, it will be also easy to support selectdim.