diff --git a/schema/functions.go b/schema/functions.go
index bda1a4f7..39756b88 100644
--- a/schema/functions.go
+++ b/schema/functions.go
@@ -39,3 +39,14 @@ func FunctionsForVersion(v *version.Version) (map[string]schema.FuncSignature, e
 	// TODO return funcs_v0_12.Functions(ver) instead?
 	return nil, errors.New("no matching functions found")
 }
+
+func FunctionsForConstraint(vc version.Constraints) (map[string]schema.FuncSignature, error) {
+	for _, v := range terraformVersions {
+		if vc.Check(v) {
+			return FunctionsForVersion(v)
+		}
+	}
+
+	// TODO create error struct
+	return nil, errors.New("no matching functions found")
+}