cpp-dice-roller/include/exception.h

//
//  exception.h
//  dice-roll
//
//  Created by Sam Jaffe on 12/1/18.
//  Copyright © 2018 Sam Jaffe. All rights reserved.
//

#pragma once

#include <stdexcept>

namespace dice {
  class unexpected_token : public std::runtime_error {
  public:
    /**
     * @brief An error for failure to parse a string into a dice::dice object
     * @param reason The specific reason that this error occured
     * @param position The index into the string that the error was located at,
     * or -1(EOF) if the error was a 'we ran out of buffer' type.
     */
    unexpected_token(std::string const & reason, long long position);
    
    /**
     * @brief Create a string matching the regex '~*^', that points to the error
     * covered by this exception class.
     * @param backup_length If {@see unexpected_token::position} == -1, use
     * this value instead as N.
     * @return A string of N '~' and one '^', pointing to the character in the
     * parse string that the error occured at.
     * "<END>" if position and backup_length are both -1
     */
    std::string pointer(long long backup_length = -1) const;
    
  private:
    long long position;
  };
}