diff --git a/lib.nix b/lib.nix
index f8be15e..4eb910d 100644
--- a/lib.nix
+++ b/lib.nix
@@ -32,7 +32,8 @@ let
   getType = expr: if isAttrs expr && expr ? _type then expr._type else null;
 
   validString = expr:
-    if isString expr || isPath expr then toString expr
+    if isRaw expr then validString expr.raw
+    else if isString expr || isPath expr then toString expr
     else error "Value '${toString expr}' is not a valid string";
 
   validFuncName = fnName:
@@ -93,7 +94,7 @@ let
   kw_while = raw "while";
   kw_repeat = raw "repeat";
 
-  op = operation: left: right: wrapParen (join " ${operation} " [ left right ]);
+  op = operation: left: right: wrapParen (join " ${validString operation} " [ left right ]);
 
   add = op "+";
   sub = op "-";
@@ -203,4 +204,6 @@ in
   # useful aliases
   var = raw;
   vars = map raw;
+
+  inherit validString;
 }
diff --git a/lib.test.nix b/lib.test.nix
index 4568745..26465b0 100644
--- a/lib.test.nix
+++ b/lib.test.nix
@@ -162,6 +162,12 @@ with nix2lua; pkgs.lib.runTests {
       (10 > 5)
     '';
   };
+  "test returns rendered condition" = {
+    expr = toLua (set "name"
+      (and (gte (var "a") 1) (lte (var "a") 10))
+    );
+    expected = "name = ((a >= 1) and (a <= 10))";
+  };
   "test returns defined function" = {
     expr = toLua (func "hello" [ "a" "b" ] [
       (eq (mul (add (var "a") 2) (sub 2 1)) 3)