chore: flat out the file structure

include/furas/gen.hpp

@@ -0,0 +1,36 @@
+#ifndef FURAS_GEN_HPP
+#define FURAS_GEN_HPP
+
+#include "furas/lexer.hpp"
+#include "furvm/module.hpp"
+
+#include <string>
+
+namespace furas {
+
+struct generator_error {
+    enum type {
+        Success = 0,
+        Eof     = 1,
+
+        UnexpectedEof    = -1,
+        UnexpectedToken  = -2,
+        UnknownCharacter = -3,
+        UnknownType      = -4,
+    } type = Success;
+    std::string message;
+};
+
+class generator {
+public:
+    struct result {
+        generator_error error;
+        furvm::mod      mod;
+    };
+public:
+    static result generate(lexer lexer);
+};
+
+} // namespace furas
+
+#endif // FURAS_GEN_HPP