/TeXmacs-1.0.7.11-src/src/Kernel/Containers/promise.hpp
C++ Header | 51 lines | 35 code | 7 blank | 9 comment | 4 complexity | 61210874287f028cbd1111aad3f93a2f MD5 | raw file
Possible License(s): GPL-3.0, GPL-2.0, MPL-2.0-no-copyleft-exception
- /******************************************************************************
- * MODULE : promise.hpp
- * DESCRIPTION: promises
- * COPYRIGHT : (C) 2007 Joris van der Hoeven
- *******************************************************************************
- * This software falls under the GNU general public license version 3 or later.
- * It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
- * in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
- ******************************************************************************/
- #ifndef PROMISE_H
- #define PROMISE_H
- #include "tree.hpp"
- class tree;
- template<class T> class promise_rep;
- template<class T> class promise;
- template<class T> tm_ostream& operator << (tm_ostream& out, promise<T> cmd);
- template<class T> bool is_nil (promise<T> l);
- template<class T>
- class promise_rep: public abstract_struct {
- public:
- inline promise_rep () {}
- inline virtual ~promise_rep () {}
- inline virtual tm_ostream& print (tm_ostream& out);
- virtual T eval () = 0;
- };
- template<class T>
- class promise {
- public:
- ABSTRACT_NULL_TEMPLATE(promise,T);
- inline T operator () ();
- friend tm_ostream& operator << LESSGTR (tm_ostream& out, promise<T> cmd);
- };
- ABSTRACT_NULL_TEMPLATE_CODE(promise,class,T);
- #define TMPL template<class T>
- TMPL inline tm_ostream& promise_rep<T>::print (tm_ostream& out) {
- return out << "promise"; }
- TMPL inline T promise<T>::operator () () {
- return rep->eval (); }
- TMPL inline bool operator == (promise<T> mw1, promise<T> mw2) {
- return mw1.rep == mw2.rep; }
- TMPL inline tm_ostream& operator << (tm_ostream& out, promise<T> cmd) {
- if (is_nil (cmd)) return out << "(null)"; else return cmd->print(out); }
- #undef TMPL
- #endif // defined PROMISE_H