Line data    Source code

       1              : /*
       2              :  * Copyright (c) 2014-2015:  G-CSC, Goethe University Frankfurt
       3              :  * Author: Martin Rupp
       4              :  * 
       5              :  * This file is part of UG4.
       6              :  * 
       7              :  * UG4 is free software: you can redistribute it and/or modify it under the
       8              :  * terms of the GNU Lesser General Public License version 3 (as published by the
       9              :  * Free Software Foundation) with the following additional attribution
      10              :  * requirements (according to LGPL/GPL v3 §7):
      11              :  * 
      12              :  * (1) The following notice must be displayed in the Appropriate Legal Notices
      13              :  * of covered and combined works: "Based on UG4 (www.ug4.org/license)".
      14              :  * 
      15              :  * (2) The following notice must be displayed at a prominent place in the
      16              :  * terminal output of covered works: "Based on UG4 (www.ug4.org/license)".
      17              :  * 
      18              :  * (3) The following bibliography is recommended for citation and must be
      19              :  * preserved in all covered files:
      20              :  * "Reiter, S., Vogel, A., Heppner, I., Rupp, M., and Wittum, G. A massively
      21              :  *   parallel geometric multigrid solver on hierarchically distributed grids.
      22              :  *   Computing and visualization in science 16, 4 (2013), 151-164"
      23              :  * "Vogel, A., Reiter, S., Rupp, M., Nägel, A., and Wittum, G. UG4 -- a novel
      24              :  *   flexible software system for simulating pde based models on high performance
      25              :  *   computers. Computing and visualization in science 16, 4 (2013), 165-179"
      26              :  * 
      27              :  * This program is distributed in the hope that it will be useful,
      28              :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      29              :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
      30              :  * GNU Lesser General Public License for more details.
      31              :  */
      32              : 
      33              : #ifndef STRINGIFY_H_
      34              : #define STRINGIFY_H_
      35              : 
      36              : #include <sstream>
      37              : 
      38              : /**
      39              :  * use this class like this
      40              :  * std::string myTmpString = Stringify() << "My_" << iInteger << "_SuperString" << ".txt";
      41              :  * also in functions
      42              :  * CallStdStringFunction(Stringify() << "My_" << iInteger << "_SuperString" << ".txt");
      43              :  * Note that this can NOT work for const char * functions, since you need an
      44              :  * temporary object which is valid for the whol call of the function.
      45              :  * Then you'd do
      46              :  * std::string myTmpString = Stringify() << "My_" << iInteger << "_SuperString" << ".txt";
      47              :  * CallConstCharFunction(myTmpString.c_str());
      48              :  * \note be sure that the object c_str is referring to is valid.
      49              :  * According to the C++ standard,
      50              :  * "Temporary objects are destroyed as the last step in evaluating the full-expression (1.9) that (lexically) contains the point where they were created. [12.2/3]"
      51              :  * so you can also do
      52              :  * CallConstCharFunction((Stringify() << "bla").c_str());
      53              :  * however,
      54              :  * const char *str = (Stringify() << "bla").c_str());
      55              :  * will NOT work.
      56              :  *
      57              :  * You can use mkstr as a wrapper around Stringify like this:
      58              :  * \code
      59              :  * std::string s = mkstr("Hello " << 5 << " is a number");
      60              :  * \endcode
      61              :  *
      62              :  * \sa mkstr
      63              :  */
      64            3 : class Stringify
      65              : {
      66              : public:
      67              :         std::stringstream ss;
      68              :         Stringify()
      69            3 :         {
      70              : 
      71            3 :         }
      72              :         template<typename T>
      73              :         Stringify &operator << (T t)
      74              :         {
      75            3 :                 ss << t;
      76              :                 return *this;
      77              :         }
      78              : 
      79              :         std::string str() const
      80              :         {
      81            3 :                 return ss.str();
      82              :         }
      83              : 
      84              :         operator std::string() const
      85              :         {
      86            0 :                 return str();
      87              :         }
      88              : };
      89              : 
      90              : ///     Comfortable (but not necessarily efficient) string building
      91              : /** Based on Stringify, mkstr allows you to easily join strings and convert
      92              :  * strings to numbers like this:
      93              :  *
      94              :  * \code
      95              :  * std::string s = mkstr("Hello " << 5 << " is a number");
      96              :  * \endcode
      97              :  *
      98              :  * Note that mkstr is not highly efficient. It should only be used in code
      99              :  * which is not performance critical.*/
     100              : #define mkstr(s)        (Stringify() << s).str()
     101              : 
     102              : 
     103              : #endif /* STRINGIFY_H_ */