diff --git a/var.go b/var.go
index b797c42..e5bf6b4 100644
--- a/var.go
+++ b/var.go
@@ -20,6 +20,13 @@ type VarName string
 // VarKind specifies special kinds of values, affects formatting.
 type VarKind int
 
+const (
+	KindDefault VarKind = iota
+	KindMemory
+	KindDuration
+	KindString
+)
+
 // Var represents arbitrary value for variable.
 type Var interface {
 	Kind() VarKind
@@ -144,13 +151,6 @@ func NewVar(name VarName) Var {
 	}
 }
 
-const (
-	KindDefault VarKind = iota
-	KindMemory
-	KindDuration
-	KindString
-)
-
 // ToSlice converts "dot-separated" notation into the "slice of strings".
 //
 // "dot-separated" notation is a human-readable format, passed via args.
diff --git a/var_test.go b/var_test.go
index 327ee8d..6c3bf08 100644
--- a/var_test.go
+++ b/var_test.go
@@ -93,6 +93,21 @@ func TestVarName(t *testing.T) {
 	}
 }
 
+func TestVarNew(t *testing.T) {
+	v := NewVar(VarName("mem:field.Subfield"))
+	if v.Kind() != KindMemory {
+		t.Fatalf("Expect Memory, got %v", v.Kind())
+	}
+	v = NewVar(VarName("str:field.Subfield"))
+	if v.Kind() != KindString {
+		t.Fatalf("Expect String, got %v", v.Kind())
+	}
+	v = NewVar(VarName("duration:field.Subfield"))
+	if v.Kind() != KindDuration {
+		t.Fatalf("Expect Duration, got %v", v.Kind())
+	}
+}
+
 func str2val(t *testing.T, s string) *jason.Value {
 	val, err := jason.NewValueFromReader(strings.NewReader(s))
 	if err != nil {
@@ -116,6 +131,7 @@ func TestVarNumber(t *testing.T) {
 	testNumber(t, v, "142", 142, "142.00")
 	testNumber(t, v, "13.24", 13, "13.24")
 	testNumber(t, v, "true", 0, "0.00")
+	testNumber(t, v, "\"success\"", 0, "0.00")
 }
 
 func TestVarMemory(t *testing.T) {
@@ -170,4 +186,8 @@ func TestVarString(t *testing.T) {
 	if want := "success"; v.String() != want {
 		t.Fatalf("Expect value to be %s, got %s", want, v.String())
 	}
+	v.Set(str2val(t, "123"))
+	if want := "N/A"; v.String() != want {
+		t.Fatalf("Expect value to be %s, got %s", want, v.String())
+	}
 }