X-Git-Url: https://ginac.de/ginac.git//ginac.git?a=blobdiff_plain;f=ginac%2Frelational.h;h=c8044f581bdd9728a17e4aec4e83671cf6670aa8;hb=dcc848e23e4d793b2b1095012a8951f5245a68d5;hp=c988a631f2e59fad825badbeee29e62073f0d905;hpb=1bd972bf8e4eeeb8aec6081100876e81a7f18450;p=ginac.git diff --git a/ginac/relational.h b/ginac/relational.h index c988a631..c8044f58 100644 --- a/ginac/relational.h +++ b/ginac/relational.h @@ -3,7 +3,7 @@ * Interface to relations between expressions. */ /* - * 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 @@ -26,9 +26,7 @@ #include "basic.h" #include "ex.h" -#ifndef NO_NAMESPACE_GINAC namespace GiNaC { -#endif // ndef NO_NAMESPACE_GINAC /** This class holds a relation consisting of two expressions and a logical * relation between them. */ @@ -47,25 +45,26 @@ public: greater_or_equal }; - // other constructors + // other ctors public: relational(const ex & lhs, const ex & rhs, operators oper=equal); - // functions overriding virtual functions from bases classes + // functions overriding virtual functions from base classes public: - void print(std::ostream & os, unsigned upper_precedence=0) const; - void printraw(std::ostream & os) const; - void printcsrc(std::ostream & os, unsigned type, unsigned upper_precedence=0) const; + void print(const print_context & c, unsigned level = 0) const; + unsigned precedence(void) const {return 20;} bool info(unsigned inf) const; - unsigned nops() const; - ex & let_op(int i); + size_t nops() const; + ex op(size_t i) const; + ex map(map_function & f) const; ex eval(int level=0) const; - ex evalf(int level=0) const; - ex normal(lst &sym_lst, lst &repl_lst, int level=0) const; - ex simplify_ncmul(const exvector & v) const; + protected: + ex eval_ncmul(const exvector & v) const; + bool match_same_type(const basic & other) const; unsigned return_type(void) const; unsigned return_type_tinfo(void) const; + unsigned calchash(void) const; // new virtual functions which can be overridden by derived classes public: @@ -73,26 +72,45 @@ public: virtual ex rhs(void) const; // non-virtual functions in this class -public: - operator bool(void) const; +private: + // For conversions to boolean, as would be used in an if conditional, + // implicit conversions from bool to int have a large number of + // undesirable side effects. The following safe_bool type enables + // use of relational objects in conditionals without those side effects + struct safe_bool_helper { + void nonnull() {}; + }; + + typedef void (safe_bool_helper::*safe_bool)(); + safe_bool make_safe_bool(bool) const; + +public: + operator safe_bool(void) const; + safe_bool operator!(void) const; + // member variables protected: ex lh; ex rh; operators o; - static unsigned precedence; }; // utility functions -inline const relational &ex_to_relational(const ex &e) + +/** Specialization of is_exactly_a(obj) for relational objects. */ +template<> inline bool is_exactly_a(const basic & obj) +{ + return obj.tinfo()==TINFO_relational; +} + +// inlined functions for efficiency +inline relational::safe_bool relational::operator!() const { - return static_cast(*e.bp); + return make_safe_bool(!static_cast(*this)); } -#ifndef NO_NAMESPACE_GINAC } // namespace GiNaC -#endif // ndef NO_NAMESPACE_GINAC #endif // ndef __GINAC_RELATIONAL_H__