Add basic app interface

- Add pool struct for data pools

include/binding/ruby.h

@@ -7,7 +7,20 @@ struct Block {
   mrb_value proc;
 
   Block(mrb_value proc) : proc(proc) {
-    mrb_gc_protect(mrb, proc);
+    mrb_gc_register(mrb, proc);
+  }
+
+  Block() : proc(mrb_nil_value()) {}
+
+  Block(const Block &) = delete;
+  Block &operator=(const Block &) = delete;
+
+  mrb_value call(int argc = 0, mrb_value *argv = nullptr) const {
+    return mrb_funcall(mrb, proc, "call", argc, argv);
+  }
+
+  ~Block() {
+    mrb_gc_unregister(mrb, proc);
   }
 };
 }; // namespace Ruby