src/rpn.h

   1 #ifndef _RPN_H_
   2 #define _RPN_H_
   3
   4 #include <list>
   5 #include <map>
   6 #include <stack>
   7 #include <string>
   8 using namespace std;
   9
  10 namespace RPN
  11 {
  12         // forward declarations.
  13         class Calculator;
  14         class Command;
  15         class Operator;
  16
  17         typedef long double Value;
  18         typedef map<string, Command>   Commands;
  19         typedef map<string, Operator>  Operators;
  20         typedef map<string, Value>     Variables;
  21         typedef stack<Value>           Stack;
  22         typedef stack<Stack>           History;
  23
  24         class Calculator
  25         {
  26                 Commands  commands;
  27                 History   history;
  28                 Operators operators;
  29                 Variables variables;
  30         public:
  31                 Calculator();
  32                 void Eval(string input);
  33         };
  34
  35         class Operator
  36         {
  37         public:
  38                 virtual operator()(Value a, Value b) = 0;
  39         };
  40
  41         class Command
  42         {
  43         public:
  44                 virtual unsigned int Arguments() = 0;
  45                 virtual operator()(Calculator& calculator, list<string>& args) = 0;
  46         };
  47 }
  48
  49 #endif // _RPN_H_