FormulaAST.h

#pragma once

  #include "FormulaLexer.h"
  #include "common.h"

  #include <forward_list>
  #include <functional>
  #include <stdexcept>

  namespace ASTImpl {
  class Expr;
  }

  class ParsingError : public std::runtime_error {
      using std::runtime_error::runtime_error;
  };

  using SheetArgs = std::function<double(Position)>;

  class FormulaAST {
  public:
      explicit FormulaAST(std::unique_ptr<ASTImpl::Expr> root_expr,
                          std::forward_list<Position> cells);
      FormulaAST(FormulaAST&&) = default;
      FormulaAST& operator=(FormulaAST&&) = default;
      ~FormulaAST();

      double Execute(const SheetArgs&) const;
      void PrintCells(std::ostream& out) const;
      void Print(std::ostream& out) const;
      void PrintFormula(std::ostream& out) const;

      std::forward_list<Position>& GetCells() {
          return cells_;
      }

      const std::forward_list<Position>& GetCells() const {
          return cells_;
      }

  private:
      std::unique_ptr<ASTImpl::Expr> root_expr_;
      std::forward_list<Position> cells_;
  };

  FormulaAST ParseFormulaAST(std::istream& in);
  FormulaAST ParseFormulaAST(const std::string& in_str);