Added validator to catch more syntax errors in pattern code

include/parser/validator.hpp

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <hex.hpp>
+
+#include "token.hpp"
+#include "ast_node.hpp"
+
+#include <string>
+#include <vector>
+
+namespace hex::lang {
+
+    class Validator {
+    public:
+        Validator();
+
+        bool validate(const std::vector<ASTNode*>& ast);
+    };
+
+}