implement to_vec for data types

Author: Miha Zgubic

src/to_vec.jl

@@ -235,6 +235,13 @@ function to_vec(d::Dict)
     return d_vec, Dict_from_vec
 end
 
+# types
+function FiniteDifferences.to_vec(x::DataType)
+    function DataType_from_vec(x_vec::Vector)
+        return x
+    end
+    return Bool[], DataType_from_vec
+end
 
 # ChainRulesCore Differentials
 function FiniteDifferences.to_vec(x::Tangent{P}) where{P}

test/to_vec.jl

@@ -195,6 +195,11 @@ end
         end
     end
 
+    @testset "DataType" begin
+        test_to_vec(Float64) # isa DataType
+        test_to_vec(Vector) # isa UnionAll
+    end
+
     @testset "ChainRulesCore Differentials" begin
         @testset "Tangent{Tuple}" begin
             @testset "basic" begin