more validators

validators/symbol.ts

@@ -0,0 +1,14 @@
+import { Validator, Args } from "../mod.ts";
+
+export const isSymbol: Validator = {
+  type: "isSymbol",
+  check: (value: any) => {
+    if (value === null || value === undefined) return;
+    if (typeof value !== "symbol") {
+      return {};
+    }
+  },
+  message: (value: any, args?: Args) => {
+    return `This value has to be a symbol.`;
+  },
+};