00001 /* 00002 expression.hh, copyright (c) 2006 by Vincent Fourmond: 00003 The main header file for SCalc. 00004 00005 This program is free software; you can redistribute it and/or modify 00006 it under the terms of the GNU General Public License as published by 00007 the Free Software Foundation; either version 2 of the License, or 00008 (at your option) any later version. 00009 00010 This program is distributed in the hope that it will be useful, 00011 but WITHOUT ANY WARRANTY; without even the implied warranty of 00012 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00013 GNU General Public License for more details (in the COPYING file). 00014 00015 */ 00016 00017 namespace SCalc { 00018 // I like Javadoc-like comments the best 00019 00020 class Expression; 00021 class FuncDef; 00022 class SyntaxError; 00023 00036 class ParserResult { 00038 Session * sess; 00039 public: 00041 ParserResult(Session * s) {sess = s;}; 00042 virtual ~ParserResult() {;}; 00043 00048 Session * session() { return sess;}; 00049 00050 // A whole set of what am I functions, all returning false 00051 // (so that the children don't actually need to redefine anything. 00052 00053 00055 00056 00057 00058 00059 00060 00065 virtual int is_expression() { return 0;} 00066 00071 Expression * to_expression() { 00072 if(is_expression()) 00073 return (Expression *) this; 00074 else 00075 return NULL; 00076 }; 00077 00078 00083 virtual int is_syntax_error() { return 0;} 00084 00089 SyntaxError * to_syntax_error() { 00090 if(is_syntax_error()) 00091 return (SyntaxError *) this; 00092 else 00093 return NULL; 00094 }; 00095 00100 virtual int is_func_def() { return 0;} 00101 00106 FuncDef * to_func_def() { 00107 if(is_func_def()) 00108 return (FuncDef *) this; 00109 else 00110 return NULL; 00111 }; 00112 00114 00115 00117 virtual std::string pretty_print() = 0; 00118 00121 virtual int can_delete() { return 1;}; 00122 }; 00123 00124 00131 class Expression : public ParserResult{ 00132 public: 00133 Expression(Session * s) : ParserResult(s) {;}; 00134 virtual ~Expression() {;}; 00135 00137 virtual int is_expression() { return 1;}; 00138 00155 virtual double evaluate(const double * values, 00156 const double * s = NULL) = 0; 00157 00163 virtual void dump(::std::ostream & stream = ::std::cerr); 00164 00170 virtual std::set<int> used_variables() { std::set<int> a; return a;}; 00171 00173 int evaluable() { return session()->evaluable(this);}; 00175 double evaluate(); 00176 00179 virtual int is_null() { return 0;}; 00180 00182 virtual int is_id() { return 0;}; 00183 00185 virtual int is_const() { return 0;}; 00186 00189 virtual int is_valid() { return 1;}; 00190 00204 virtual Expression * derive(int id); 00205 00207 virtual Expression * copy() { return NULL;}; 00208 00215 virtual std::string pretty_print() = 0; 00216 00217 00228 virtual Expression * simplify() { return copy();}; 00229 00242 virtual double * mass_evaluate(int nb, double * target, const double **variables); 00243 00249 00251 static Expression * add(Expression *, Expression* ); 00252 static Expression * sub(Expression *, Expression* ); 00253 static Expression * mul(Expression *, Expression* ); 00254 static Expression * div(Expression *, Expression* ); 00257 }; 00258 00259 00260 }; 00261
1.7.1