diff --git a/pkg/eval/compile_effect_test.go b/pkg/eval/compile_effect_test.go
index a06d210f..0dfb431d 100644
--- a/pkg/eval/compile_effect_test.go
+++ b/pkg/eval/compile_effect_test.go
@@ -135,8 +135,8 @@ func TestCommand_Assignment(t *testing.T) {
 		// Assignment errors when the RHS errors.
 		That("x = [][1]").Throws(ErrorWithType(errs.OutOfRange{}), "[][1]"),
 		// Assignment errors itself.
-		That("true = 1").Throws(vars.ErrSetReadOnlyVar, "true = 1"),
-		That("@true = 1").Throws(vars.ErrSetReadOnlyVar, "@true = 1"),
+		That("true = 1").Throws(vars.ErrSetReadOnlyVar, "true"),
+		That("@true = 1").Throws(vars.ErrSetReadOnlyVar, "@true"),
 		// Arity mismatch.
 		That("x = 1 2").Throws(
 			errs.ArityMismatch{
diff --git a/pkg/eval/compile_lvalue.go b/pkg/eval/compile_lvalue.go
index 02edbe1e..b7098551 100644
--- a/pkg/eval/compile_lvalue.go
+++ b/pkg/eval/compile_lvalue.go
@@ -124,7 +124,7 @@ func (op *assignOp) exec(fm *Frame) Exception {
 		for i, variable := range variables {
 			err := variable.Set(values[i])
 			if err != nil {
-				return fm.errorp(op, err)
+				return fm.errorp(op.lhs.lvalues[i], err)
 			}
 		}
 	} else {
@@ -137,18 +137,18 @@ func (op *assignOp) exec(fm *Frame) Exception {
 		for i := 0; i < rest; i++ {
 			err := variables[i].Set(values[i])
 			if err != nil {
-				return fm.errorp(op, err)
+				return fm.errorp(op.lhs.lvalues[i], err)
 			}
 		}
 		restOff := len(values) - len(variables)
 		err := variables[rest].Set(vals.MakeList(values[rest : rest+restOff+1]...))
 		if err != nil {
-			return fm.errorp(op, err)
+			return fm.errorp(op.lhs.lvalues[rest], err)
 		}
 		for i := rest + 1; i < len(variables); i++ {
 			err := variables[i].Set(values[i+restOff])
 			if err != nil {
-				return fm.errorp(op, err)
+				return fm.errorp(op.lhs.lvalues[i], err)
 			}
 		}
 	}
diff --git a/pkg/eval/ns_test.go b/pkg/eval/ns_test.go
index 7f934ae2..71e4c42a 100644
--- a/pkg/eval/ns_test.go
+++ b/pkg/eval/ns_test.go
@@ -26,6 +26,6 @@ func TestNs(t *testing.T) {
 
 func TestBuiltinFunctionsReadOnly(t *testing.T) {
 	Test(t,
-		That("return~ = { }").Throws(vars.ErrSetReadOnlyVar, "return~ = { }"),
+		That("return~ = { }").Throws(vars.ErrSetReadOnlyVar, "return~"),
 	)
 }
diff --git a/pkg/eval/pwd_test.go b/pkg/eval/pwd_test.go
index 7b3f3035..65c39a14 100644
--- a/pkg/eval/pwd_test.go
+++ b/pkg/eval/pwd_test.go
@@ -24,7 +24,7 @@ func TestBuiltinPwd(t *testing.T) {
 
 	Test(t,
 		That(`pwd=dir1 put $pwd; put $pwd`).Puts(dir1, tmpHome),
-		That(`pwd=(float64 1) put $pwd`).Throws(vars.ErrPathMustBeString, "pwd=(float64 1)"),
+		That(`pwd=(float64 1) put $pwd`).Throws(vars.ErrPathMustBeString, "pwd"),
 	)
 
 	// We could separate these two test variants into separate unit test