added example for namespace bracing

[ginac.git] / ginac / fail.h

diff --git a/ginac/fail.h b/ginac/fail.h
index f3104d85fcb7f3b6f7c7eaca73334803cf1842b8..75a75bfcc10a01921228d7e2bce23939b3882874 100644 (file)
--- a/ginac/fail.h
+++ b/ginac/fail.h
@@ -1,10 +1,10 @@
 /** @file fail.h
  *
- *  Interface to class signaling failure of operation. Considered obsolete all
- *  this stuff ought to be replaced by exceptions. */
+ *  Interface to class signaling failure of operation. Considered obsolete
+ *  somewhat obsolete (most of this can be replaced by exceptions). */
 
 /*
- *  GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -32,26 +32,21 @@ class fail : public basic
 {
        GINAC_DECLARE_REGISTERED_CLASS(fail, basic)
        
-       // other ctors
-       // none
-       
-       // functions overriding virtual functions from bases classes
-public:
-       void print(std::ostream & os, unsigned upper_precedence=0) const;
-       void printraw(std::ostream & os) const;
+       // functions overriding virtual functions from base classes
 protected:
-       unsigned return_type(void) const { return return_types::noncommutative_composite; };
-       
-       // new virtual functions which can be overridden by derived classes
-       // none
-       
+       unsigned return_type() const { return return_types::noncommutative_composite; };
+
        // non-virtual functions in this class
-       // none
-       
-       // member variables
-       // none
+protected:
+       void do_print(const print_context & c, unsigned level) const;
 };
 
+/** Specialization of is_exactly_a<fail>(obj) for fail objects. */
+template<> inline bool is_exactly_a<fail>(const basic & obj)
+{
+       return obj.tinfo()==TINFO_fail;
+}
+
 } // namespace GiNaC
 
 #endif // ndef __GINAC_FAIL_H__