diff --git a/packages/squiggle-lang/__tests__/Reducer/Reducer_MathJs/Reducer_MathJsEval_test.res b/packages/squiggle-lang/__tests__/Reducer/Reducer_MathJs/Reducer_MathJsEval_test.res
index 4b260ddf..355c69ea 100644
--- a/packages/squiggle-lang/__tests__/Reducer/Reducer_MathJs/Reducer_MathJsEval_test.res
+++ b/packages/squiggle-lang/__tests__/Reducer/Reducer_MathJs/Reducer_MathJsEval_test.res
@@ -20,7 +20,7 @@ describe("errors", () => {
   // All those errors propagete up and are returned by the resolver
   test("unknown function", () =>
     expect(MathJs.Eval.eval("testZadanga()"))->toEqual(
-      Error(ErrorValue.REJs(Some("Undefined function testZadanga"), Some("Error"))),
+      Error(ErrorValue.REJavaScriptExn(Some("Undefined function testZadanga"), Some("Error"))),
     )
   )
 
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn.res
index a6ff353c..0a84f876 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Dispatch/Reducer_Dispatch_BuiltIn.res
@@ -67,6 +67,6 @@ let dispatch = (call: functionCall): result<expressionValue, errorValue> =>
     // So we have to recreate a copy of the string
     ExternalLibrary.dispatch((Js.String.make(fn), args), callInternal)
   } catch {
-  | Js.Exn.Error(obj) => REJs(Js.Exn.message(obj), Js.Exn.name(obj))->Error
+  | Js.Exn.Error(obj) => REJavaScriptExn(Js.Exn.message(obj), Js.Exn.name(obj))->Error
   | _ => RETodo("unhandled rescript exception")->Error
   }
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res
index 3b318083..d026765d 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_ErrorValue.res
@@ -1,7 +1,7 @@
 type errorValue =
   | REArrayIndexNotFound(string, int)
   | REFunctionExpected(string)
-  | REJs(option<string>, option<string>) // Javascript Exception
+  | REJavaScriptExn(option<string>, option<string>) // Javascript Exception
   | RERecordPropertyNotFound(string, string)
   | RETodo(string) // To do
 
@@ -9,7 +9,7 @@ let showError = err =>
   switch err {
   | REArrayIndexNotFound(msg, index) => `${msg}: ${Js.String.make(index)}`
   | REFunctionExpected(msg) => `Function expected: ${msg}`
-  | REJs(omsg, oname) => {
+  | REJavaScriptExn(omsg, oname) => {
       let answer = "JS Exception:"
       let answer = switch oname {
       | Some(name) => `${answer} ${name}`
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Eval.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Eval.res
index b99a3201..94a1834c 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Eval.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Eval.res
@@ -22,6 +22,6 @@ let eval = (expr: string): result<expressionValue, errorValue> => {
     let answer = eval__(expr)
     answer["value"]->JavaScript.Gate.jsToEv
   } catch {
-  | Js.Exn.Error(obj) => REJs(Js.Exn.message(obj), Js.Exn.name(obj))->Error
+  | Js.Exn.Error(obj) => REJavaScriptExn(Js.Exn.message(obj), Js.Exn.name(obj))->Error
   }
 }
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Parse.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Parse.res
index 26484cf4..2eb88129 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Parse.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_MathJs/Reducer_MathJs_Parse.res
@@ -44,7 +44,7 @@ let parse = (expr: string): result<node, errorValue> =>
   try {
     Ok(parse__(expr))
   } catch {
-  | Js.Exn.Error(obj) => REJs(Js.Exn.message(obj), Js.Exn.name(obj))->Error
+  | Js.Exn.Error(obj) => REJavaScriptExn(Js.Exn.message(obj), Js.Exn.name(obj))->Error
   }
 
 type mathJsNode =