interpreter_tree first iteration

include/contexts.hpp

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include <unordered_map>
+
+// for clangd
+#include "symbols_info.hpp"
+
+namespace info {
+
+class ContextManager {
+public:
+  void CallFunction(const std::vector<VariableInfo>&);
+  void EnterContext();
+  void ExitContext();
+
+  void DefineVariable(const VariableInfo& variable);
+  void ChangeVariableValue(const std::string& name, const Value& new_value);
+  const Value& GetVariableValue(const std::string& name);
+private:
+  class Context {
+  public:
+    Context(bool hide_previous = false) : hide_previous_(hide_previous) {}
+
+    void DefineVariable(const VariableInfo& variable);
+    void ChangeVaraibleValue(const std::string& name, const Value& neew_value);
+    const Value& GetVariableValue(const std::string& name);
+
+    bool IsFirst() { return hide_previous_; }
+  private:
+    bool hide_previous_;
+    std::unordered_map<std::string, VariableInfo> variables_;
+  };
+
+  // TODO handle current namespace (for class names, function names, etc.)
+  // TODO ?? are global variables forbidden ??
+
+  Context global_context_;
+  std::vector<Context> contexts_;
+};
+
+} // namespace info