interpreter_tree first iteration

include/parse_tree.hpp

@@ -0,0 +1,64 @@
+#pragma once
+
+#include <string>
+
+// for clangd
+#include "tree_sitter/api.h"
+
+
+namespace parser {
+
+class ParseTree {
+public:
+  class Node {
+  public:
+    Node() = delete;
+
+    std::string GetType();
+    std::pair<size_t, size_t> GetStartPoint();
+    std::pair<size_t, size_t> GetEndPoint();
+    std::string GetAsSExpression();
+
+    bool IsNull();
+    bool IsNamed();
+    bool IsMissing();
+    bool IsExtra(); // comments, etc.
+    bool HasError();
+
+    Node NthChild(size_t n);
+    size_t ChildCount();
+
+    Node NthNamedChild(size_t n);
+    size_t NamedChildCount();
+
+    Node ChildByName(const std::string& name);
+
+    // ?? use field id instaed of name ??
+    // ?? node equality check needed ??
+  private:
+    TSNode node_;
+  };
+  class Cursor {
+  public:
+    Cursor(const Node& node);
+
+    void ResetTo(const Node& node);
+
+    Node GetCurrentNode();
+    std::string GetCurrentNodeName();
+
+    bool GoToParent();
+    bool GoToNextSibling();
+    bool GoToFirstChild();
+  private:
+    TSTreeCursor cursor_;
+  };
+
+  ParseTree(const std::string& input);
+
+  Node GetRoot();
+private:
+  TSTree* tree_;
+};
+
+} // namespace parser