grammar_error.hpp

#pragma once
#include <stdexcept>
#include <utility>
 
class GrammarError : public std::exception {
  public:
    explicit GrammarError(std::string msg) : msg_(std::move(msg)) {}
    [[nodiscard]] const char* what() const noexcept override {
        return msg_.c_str();
    }
 
  private:
    std::string msg_;
};
class GrammarError : public std::exception {…};