diff --git a/src/libexpr/flake/flake.cc b/src/libexpr/flake/flake.cc
index 41c93bcaa..9f1e4063f 100644
--- a/src/libexpr/flake/flake.cc
+++ b/src/libexpr/flake/flake.cc
@@ -120,15 +120,19 @@ static FlakeInput parseFlakeInput(EvalState & state,
                 expectType(state, nString, *attr.value, *attr.pos);
                 input.follows = parseInputPath(attr.value->string.s);
             } else {
-                if (attr.value->type() == nString) {
-                    attrs.emplace(attr.name, attr.value->string.s);
-                } else if (attr.value->type() == nBool) {
-                    attrs.emplace(attr.name, Explicit<bool>{ attr.value->boolean });
-                } else if (attr.value->type() == nInt) {
-                    attrs.emplace(attr.name, attr.value->integer);
-                } else {
-                    throw TypeError("flake input attribute '%s' is %s while a string, boolean, or integer is expected",
-                        attr.name, showType(*attr.value));
+                switch (attr.value->type()) {
+                    case nString:
+                        attrs.emplace(attr.name, attr.value->string.s);
+                        break;
+                    case nBool:
+                        attrs.emplace(attr.name, Explicit<bool> { attr.value->boolean });
+                        break;
+                    case nInt:
+                        attrs.emplace(attr.name, attr.value->integer);
+                        break;
+                    default:
+                        throw TypeError("flake input attribute '%s' is %s while a string, boolean, or integer is expected",
+                            attr.name, showType(*attr.value));
                 }
             }
         } catch (Error & e) {