LispCons.h

   1 #if !defined(H_LISPCONS)
   2 #define H_LISPCONS
   3
   4 #include "LispNil.h"
   5 #include <utility>
   6
   7 namespace Lisp
   8 {
   9         class Cons;
  10
  11         class Cons : public Obj
  12         {
  13         public:
  14
  15                 typedef Cons* ConsPtr;
  16                 typedef Cons& ConsRef;
  17
  18                 Cons() :
  19                         value_(NIL::make(), NIL::make())
  20                 {
  21                 }
  22
  23                 Cons(const Cons& other)
  24                 {
  25                         if (this != &other)
  26                                 value_ = other.value_;
  27                 }
  28
  29                 Obj::eObjectType Cons::getObjectType() const
  30                 {
  31                         return Obj::eConsObj;
  32                 }
  33
  34
  35                 Cons* make() const
  36                 {
  37                         return new Cons();
  38                 }
  39
  40                 Cons* create() const
  41                 {
  42                         return new Cons();
  43                 }
  44
  45
  46                 Cons* clone() const
  47                 {
  48                         return new Cons(*this);
  49                 }
  50
  51                 virtual void print(std::ostream& out) const
  52                 {
  53                         out << " ";
  54                         value_.first->print(out);
  55                         out << " . ";
  56                         value_.second->print(out);
  57                         out << " ";
  58                 }
  59
  60                 bool operator==(const Obj* other)
  61                 {
  62                         bool result = false;
  63                         if (other->getObjectType() == eConsObj)
  64                                 result = ( ( value_.first == dynamic_cast<const Cons*>(other)->value_.first ) &&
  65                                                    ( value_.second == dynamic_cast<const Cons*>(other)->value_.second ) );
  66                         return result;
  67                 }
  68
  69                 Obj* car()
  70                 {
  71                         return value_.first;
  72                 }
  73
  74                 Obj* cdr()
  75                 {
  76                         return value_.second;
  77                 }
  78
  79         private:
  80
  81                 std::pair<Obj*, Obj*> value_;
  82         };
  83 }
  84
  85 #endif
  86