message: Rename get_string to move_string to imply side-effect
diff: @@ -2702,8 +2702,8 @@ scan_number_done:
  return value_float;
  }
  - /// return string value
  - std::string get_string()
  + /// return current string value (implicitly resets the token; useful only once)
  + std::string move_string()
  {
  return std::move( yytext );
  }
  @@ -3004,7 +3004,7 @@ class parser
  {
  return;
  }
  - key = m_lexer.get_string();
  + key = m_lexer.move_string();
  bool keep_tag = false;
  if (keep)
  @@ -3142,7 +3142,7 @@ class parser
  case token_type::value_string:
  {
  result.m_type = value_t::string;
  - result.m_value = m_lexer.get_string();
  + result.m_value = m_lexer.move_string();
  break;
  }
  