to_vec for inplaceablethunk (#203)

Author: mzgubic

Project.toml

@@ -1,6 +1,6 @@
 name = "FiniteDifferences"
 uuid = "26cc04aa-876d-5657-8c51-4c34ba976000"
-version = "0.12.23"
+version = "0.12.24"
 
 [deps]
 ChainRulesCore = "d360d2e6-b24c-11e9-a2a3-2a2ae2dbcce4"

src/to_vec.jl

@@ -287,3 +287,14 @@ function FiniteDifferences.to_vec(t::Thunk)
     Thunk_from_vec = v -> @thunk(back(v))
     return v, Thunk_from_vec
 end
+
+function FiniteDifferences.to_vec(t::InplaceableThunk)
+    v, back = to_vec(unthunk(t))
+    function InplaceableThunk_from_vec(v)
+        return InplaceableThunk(
+            Δ -> Δ += back(b),
+            @thunk(back(v))
+        )
+    end
+    return v, InplaceableThunk_from_vec
+end

test/to_vec.jl

@@ -249,7 +249,9 @@ end
         end
 
         @testset "Thunks" begin
-            test_to_vec(@thunk(3.2+4.3))
+            t = @thunk(3.2+4.3)
+            test_to_vec(t)
+            test_to_vec(InplaceableThunk(Δ -> Δ += t, t))
         end
     end