1 /*
2  *  Copyright (C) 2004-2021 Edward F. Valeev
3  *
4  *  This file is part of Libint.
5  *
6  *  Libint is free software: you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation, either version 3 of the License, or
9  *  (at your option) any later version.
10  *
11  *  Libint is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with Libint.  If not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20 
21 #ifndef _libint2_src_bin_libint_contract_h_
22 #define _libint2_src_bin_libint_contract_h_
23 
24 namespace libint2 {
25 
26   /// use this as a base to add to Derived a "contracted()" attribute
27   template <typename Derived> class Contractable {
28     public:
Contractable()29       Contractable() : value_(default_value_) {}
Contractable(const Contractable & source)30       Contractable(const Contractable& source) : value_(source.value_) {}
31       Contractable& operator=(const Contractable& source) {
32         value_ = source.value_;
33         return *this;
34       }
contracted()35       bool contracted() const { return value_; }
uncontract()36       void uncontract() { value_ = false; }
contract()37       void contract() { value_ = true; }
set_contracted_default_value(bool dv)38       static void set_contracted_default_value(bool dv) { default_value_ = dv; }
39     private:
40       bool value_;
41       static bool default_value_;
42   };
43   template <typename Derived>
44   bool Contractable<Derived>::default_value_ = false;
45 
46 };
47 
48 #endif
49