update travis

.travis.yml

@@ -6,7 +6,7 @@ os:
   # - osx
 
 julia:
-  - 1.0
+  - 1.1
   - nightly
 
 matrix:

src/tracker/lib/array.jl

@@ -35,10 +35,10 @@ Base.eltype(x::Type{<:TrackedArray{T}}) where T <: Real = TrackedReal{T}
 
 Base.convert(::Type{T}, x::S) where {T<:TrackedArray,S<:T} = x
 
-Base.convert(::Type{<:TrackedArray}, x::TrackedArray) =
-  error("Not implemented: convert $(typeof(x)) to $T")
+Base.convert(::Type{TrackedArray{T,N,A}}, x::TrackedArray) where {T,N,A} =
+  track(convert, A, x)
 
-Base.convert(::Type{<:TrackedArray{T,N,A}}, x::AbstractArray) where {T,N,A} =
+Base.convert(::Type{TrackedArray{T,N,A}}, x::AbstractArray) where {T,N,A} =
   TrackedArray(convert(A, x))
 
 Base.show(io::IO, t::Type{TrackedArray{T,N,A}}) where {T,N,A<:AbstractArray{T,N}} =

src/tracker/lib/real.jl

@@ -37,7 +37,9 @@ Base.convert(::Type{TrackedReal{T}}, x::TrackedReal{T}) where T = x
 Base.convert(::Type{TrackedReal{T}}, x::Real) where T = TrackedReal(convert(T, x))
 
 Base.convert(::Type{TrackedReal{T}}, x::TrackedReal{S}) where {T,S} =
-  error("Not implemented: convert tracked $S to tracked $T")
+  track(convert, T, x)
+
+@grad convert(T, x) = convert(T, data(x)), ȳ -> (nothing, convert(typeof(x), ȳ))
 
 (T::Type{<:TrackedReal})(x::Real) = convert(T, x)