class scalar_products;
class const_iterator;
+class const_preorder_iterator;
+class const_postorder_iterator;
/** Lightweight wrapper for GiNaC's symbolic objects. Basically all it does is
* to hold a pointer to the other objects, manage the reference counting and
* provide methods for manipulation of these objects. (Some people call such
* a thing a proxy class.) */
-class ex
-{
+class ex {
friend class archive_node;
friend inline bool are_ex_trivially_equal(const ex &, const ex &);
template<class T> friend inline const T &ex_to(const ex &);
// iterators
const_iterator begin() const throw();
const_iterator end() const throw();
+ const_preorder_iterator preorder_begin() const;
+ const_preorder_iterator preorder_end() const throw();
+ const_postorder_iterator postorder_begin() const;
+ const_postorder_iterator postorder_end() const throw();
// evaluation
ex eval(int level = 0) const { return bp->eval(level); }
// Iterators
-class const_iterator : public std::iterator<std::random_access_iterator_tag, ex, ptrdiff_t, const ex *, const ex &>
-{
+class const_iterator : public std::iterator<std::random_access_iterator_tag, ex, ptrdiff_t, const ex *, const ex &> {
friend class ex;
friend class const_preorder_iterator;
friend class const_postorder_iterator;
} // namespace internal
-class const_preorder_iterator : public std::iterator<std::forward_iterator_tag, ex, ptrdiff_t, const ex *, const ex &>
-{
+class const_preorder_iterator : public std::iterator<std::forward_iterator_tag, ex, ptrdiff_t, const ex *, const ex &> {
public:
const_preorder_iterator() throw() {}
- // Provide implicit conversion from const_iterator, so ex::begin() and
- // ex::end() can be used to create const_preorder_iterators
- const_preorder_iterator(const const_iterator & cit)
+ const_preorder_iterator(const ex &e, size_t n)
{
- s.push(internal::_iter_rep(cit.e, cit.i, cit.e.nops()));
+ s.push(internal::_iter_rep(e, 0, n));
}
public:
- ex operator*() const
+ reference operator*() const
{
return s.top().e;
}
- std::auto_ptr<ex> operator->() const
+ pointer operator->() const
{
- return std::auto_ptr<ex>(new ex(operator*()));
+ return &(s.top().e);
}
const_preorder_iterator &operator++()
bool operator==(const const_preorder_iterator &other) const throw()
{
- return s.top() == other.s.top();
+ return s == other.s;
}
bool operator!=(const const_preorder_iterator &other) const throw()
void increment()
{
- while (s.top().i == s.top().i_end && s.size() > 1) {
+ while (!s.empty() && s.top().i == s.top().i_end) {
s.pop();
+ if (s.empty())
+ return;
++s.top().i;
}
}
};
-class const_postorder_iterator : public std::iterator<std::forward_iterator_tag, ex, ptrdiff_t, const ex *, const ex &>
-{
+class const_postorder_iterator : public std::iterator<std::forward_iterator_tag, ex, ptrdiff_t, const ex *, const ex &> {
public:
const_postorder_iterator() throw() {}
- // Provide implicit conversion from const_iterator, so ex::begin() and
- // ex::end() can be used to create const_postorder_iterators
- const_postorder_iterator(const const_iterator & cit)
+ const_postorder_iterator(const ex &e, size_t n)
{
- size_t n = cit.e.nops();
- if (cit.i != n) {
- s.push(internal::_iter_rep(cit.e, cit.i, n));
- descend();
- }
+ s.push(internal::_iter_rep(e, 0, n));
+ descend();
}
public:
- ex operator*() const
+ reference operator*() const
{
return s.top().e;
}
- std::auto_ptr<ex> operator->() const
+ pointer operator->() const
{
- return std::auto_ptr<ex>(new ex(operator*()));
+ return &(s.top().e);
}
const_postorder_iterator &operator++()
{
if (s.top().i == s.top().i_end)
s.pop();
- if (s.size() > 0) {
+ if (!s.empty()) {
++s.top().i;
descend();
}
return const_iterator(*this, nops());
}
+inline const_preorder_iterator ex::preorder_begin() const
+{
+ return const_preorder_iterator(*this, nops());
+}
+
+inline const_preorder_iterator ex::preorder_end() const throw()
+{
+ return const_preorder_iterator();
+}
+
+inline const_postorder_iterator ex::postorder_begin() const
+{
+ return const_postorder_iterator(*this, nops());
+}
+
+inline const_postorder_iterator ex::postorder_end() const throw()
+{
+ return const_postorder_iterator();
+}
+
// utility functions