/*=============================================================================
Wave: A Standard compliant C++ preprocessor
Definition of the unput queue iterator
Copyright (c) 2001-2004 Hartmut Kaiser
http://spirit.sourceforge.net/
Use, modification and distribution is subject to the Boost Software
License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt)
See Copyright.txt for full acknowledgements.
=============================================================================*/
#if !defined(UNPUT_QUEUE_ITERATOR_HPP_76DA23D0_4893_4AD5_ABCC_6CED7CFB89BC_INCLUDED)
#define UNPUT_QUEUE_ITERATOR_HPP_76DA23D0_4893_4AD5_ABCC_6CED7CFB89BC_INCLUDED
#include <list>
#include <boost/iterator_adaptors.hpp>
///////////////////////////////////////////////////////////////////////////////
namespace wave {
namespace util {
#if !defined(BOOST_ITERATOR_ADAPTORS_VERSION) || \
BOOST_ITERATOR_ADAPTORS_VERSION < 0x0200
template <typename TokenT, typename ContainerT>
class unput_queue_policies : public boost::default_iterator_policies
{
public:
unput_queue_policies(ContainerT &unput_queue_)
: unput_queue(unput_queue_)
{}
unput_queue_policies &operator= (unput_queue_policies const &rhs)
{
unput_queue = rhs.unput_queue;
return *this;
}
template <typename BaseT>
void initialize(BaseT &)
{}
template <typename IteratorAdaptorT>
typename IteratorAdaptorT::reference
dereference(const IteratorAdaptorT &x) const
{
if (x.policies().unput_queue.size() > 0)
return x.policies().unput_queue.front();
return *x.base();
}
template <typename IteratorAdaptorT>
void
increment(IteratorAdaptorT &x)
{
if (x.policies().unput_queue.size() > 0) {
// there exist pending tokens in the unput queue
x.policies().unput_queue.pop_front();
}
else {
// the unput_queue is empty, so advance the base iterator
++x.base();
}
}
template <typename IteratorAdaptorT1, typename IteratorAdaptorT2>
bool
equal(const IteratorAdaptorT1 &x, const IteratorAdaptorT2 &y) const
{
// two iterators are equal, if both begin() iterators of the queue objects
// are equal and the base iterators too
return
(x.policies().unput_queue.begin() == y.policies().unput_queue.begin() ||
(0 == x.policies().queuesize() && 0 == y.policies().queuesize())) &&
x.base() == y.base();
}
typename ContainerT::size_type queuesize() const
{ return unput_queue.size(); }
ContainerT &get_unput_queue() { return unput_queue; }
private:
ContainerT &unput_queue;
};
///////////////////////////////////////////////////////////////////////////////
//
// unput_queue_iterator
//
// The unput_queue_iterator templates encapsulates an unput_queue together
// with the direct input to be read after the unput queue is emptied
//
// This version is for the old iterator_adaptors (Boost V1.30.x)
//
///////////////////////////////////////////////////////////////////////////////
template <typename IteratorT, typename TokenT, typename ContainerT>
class unput_queue_iterator
: public boost::iterator_adaptor<
IteratorT, unput_queue_policies<TokenT, ContainerT>, TokenT,
TokenT const &, TokenT const *>
{
typedef
boost::iterator_adaptor<
IteratorT, unput_queue_policies<TokenT, ContainerT>, TokenT,
TokenT const &, TokenT const *
>
base_t;
typedef unput_queue_policies<TokenT, ContainerT> policies_t;
public:
typedef ContainerT container_t;
typedef IteratorT iterator_t;
unput_queue_iterator(IteratorT const &it, ContainerT &queue)
: base_t(it, policies_t(queue))
{}
ContainerT &get_unput_queue() { return policies().get_unput_queue(); }
IteratorT &get_base_iterator() { return base(); }
};
#else // BOOST_ITERATOR_ADAPTORS_VERSION < 0x0200
///////////////////////////////////////////////////////////////////////////////
//
// unput_queue_iterator
//
// The unput_queue_iterator templates encapsulates an unput_queue together
// with the direct input to be read after the unput queue is emptied
//
// This version is for the new iterator_adaptors (should be released with
// Boost V1.31.0)
//
///////////////////////////////////////////////////////////////////////////////
template <typename IteratorT, typename TokenT, typename ContainerT>
class unput_queue_iterator
: public boost::iterator_adaptor<
unput_queue_iterator<IteratorT, TokenT, ContainerT>,
IteratorT, TokenT const, std::forward_iterator_tag>
{
typedef boost::iterator_adaptor<
unput_queue_iterator<IteratorT, TokenT, ContainerT>,
IteratorT, TokenT const, std::forward_iterator_tag>
base_t;
public:
typedef ContainerT container_t;
typedef IteratorT iterator_t;
unput_queue_iterator(IteratorT const &it, ContainerT &queue)
: base_t(it), unput_queue(queue)
{}
ContainerT &get_unput_queue() { return unput_queue; }
ContainerT const &get_unput_queue() const { return unput_queue; }
IteratorT &get_base_iterator() { return base_reference(); }
IteratorT const &get_base_iterator() const { return base_reference(); }
unput_queue_iterator &operator= (unput_queue_iterator const &rhs)
{
if (this != &rhs) {
unput_queue = rhs.unput_queue;
base_t::operator=(rhs);
}
return *this;
}
typename base_t::reference dereference() const
{
if (unput_queue.size() > 0)
return unput_queue.front();
return *base_reference();
}
void increment()
{
if (unput_queue.size() > 0) {
// there exist pending tokens in the unput queue
unput_queue.pop_front();
}
else {
// the unput_queue is empty, so advance the base iterator
++base_reference();
}
}
template <
typename OtherDerivedT, typename OtherIteratorT,
typename V, typename C, typename R, typename D
>
bool equal(
boost::iterator_adaptor<OtherDerivedT, OtherIteratorT, V, C, R, D>
const &x) const
{
// two iterators are equal, if both begin() iterators of the queue objects
// are equal and the base iterators too
OtherDerivedT const &rhs = static_cast<OtherDerivedT const &>(x);
return
(unput_queue.begin() == rhs.get_unput_queue().begin() ||
(0 == unput_queue.size() && 0 == rhs.get_unput_queue().size())) &&
get_base_iterator() == rhs.get_base_iterator();
}
private:
ContainerT &unput_queue;
};
#endif // BOOST_ITERATOR_ADAPTORS_VERSION < 0x0200
namespace impl {
///////////////////////////////////////////////////////////////////////////
template <typename IteratorT, typename TokenT, typename ContainerT>
struct gen_unput_queue_iterator {
typedef unput_queue_iterator<IteratorT, TokenT, ContainerT> return_t;
static return_t
generate(ContainerT &queue, IteratorT const &it)
{
return return_t(it, queue);
}
};
template <typename IteratorT, typename TokenT, typename ContainerT>
struct gen_unput_queue_iterator<
unput_queue_iterator<IteratorT, TokenT, ContainerT>,
TokenT, ContainerT>
{
typedef unput_queue_iterator<IteratorT, TokenT, ContainerT> return_t;
static return_t
generate(ContainerT &queue, return_t const &it)
{
return return_t(it.base(), queue);
}
};
///////////////////////////////////////////////////////////////////////////
template <typename IteratorT>
struct assign_iterator {
static void
do_ (IteratorT &dest, IteratorT const &src)
{
dest = src;
}
};
#if !defined(BOOST_ITERATOR_ADAPTORS_VERSION) || \
BOOST_ITERATOR_ADAPTORS_VERSION < 0x0200
template <typename IteratorT, typename TokenT, typename ContainerT>
struct assign_iterator<
unput_queue_iterator<IteratorT, TokenT, ContainerT> >
{
typedef unput_queue_iterator<IteratorT, TokenT, ContainerT> iterator_t;
static void
do_ (iterator_t &dest, iterator_t const &src)
{
dest.base() = src.base();
dest.policies() = src.policies();
}
};
#endif // BOOST_ITERATOR_ADAPTORS_VERSION < 0x0200
///////////////////////////////////////////////////////////////////////////
//
// Look for the first non-whitespace token and return this token id.
// Note though, that the embedded unput_queues are not touched in any way!
//
template <typename IteratorT>
struct next_token {
static WAVE_LEXER_NS::token_id
peek(IteratorT it, IteratorT end, bool skip_whitespace = true)
{
using namespace WAVE_LEXER_NS;
if (skip_whitespace) {
for (++it; it != end; ++it) {
if (!IS_CATEGORY(*it, WhiteSpaceTokenType) &&
T_NEWLINE != token_id(*it))
{
break; // stop at the first non-whitespace token
}
}
}
else {
++it; // we have at least to look ahead
}
if (it != end)
return token_id(*it);
return T_EOI;
}
};
template <typename IteratorT, typename TokenT, typename ContainerT>
struct next_token<
unput_queue_iterator<IteratorT, TokenT, ContainerT> > {
typedef unput_queue_iterator<IteratorT, TokenT, ContainerT> iterator_t;
static WAVE_LEXER_NS::token_id
peek(iterator_t it, iterator_t end, bool skip_whitespace = true)
{
using namespace WAVE_LEXER_NS;
typename iterator_t::container_t &queue = it.get_unput_queue();
// first try to find it in the unput_queue
if (0 != queue.size()) {
typename iterator_t::container_t::iterator cit = queue.begin();
typename iterator_t::container_t::iterator cend = queue.end();
if (skip_whitespace) {
for (++cit; cit != cend; ++cit) {
if (!IS_CATEGORY(*cit, WhiteSpaceTokenType) &&
T_NEWLINE != token_id(*cit))
{
break; // stop at the first non-whitespace token
}
}
}
else {
++cit; // we have at least to look ahead
}
if (cit != cend)
return token_id(*cit);
}
// second try to move on into the base iterator stream
typename iterator_t::iterator_t base_it = it.get_base_iterator();
typename iterator_t::iterator_t base_end = end.get_base_iterator();
if (0 == queue.size())
++base_it; // advance, if the unput queue is empty
if (skip_whitespace) {
for (/**/; base_it != base_end; ++base_it) {
if (!IS_CATEGORY(*base_it, WhiteSpaceTokenType) &&
T_NEWLINE != token_id(*base_it))
{
break; // stop at the first non-whitespace token
}
}
}
if (base_it == base_end)
return T_EOI;
return token_id(*base_it);
}
};
// Skip all whitespace characters and queue the skipped characters into the
// given container
template <typename IteratorT>
inline WAVE_LEXER_NS::token_id
skip_whitespace(IteratorT &first, IteratorT const &last)
{
using namespace cpplexer;
token_id id = next_token<IteratorT>::peek(first, last, false);
if (IS_CATEGORY(id, WhiteSpaceTokenType)) {
do {
++first;
id = next_token<IteratorT>::peek(first, last, false);
} while (IS_CATEGORY(id, WhiteSpaceTokenType));
}
++first;
return id;
}
template <typename IteratorT, typename ContainerT>
inline WAVE_LEXER_NS::token_id
skip_whitespace(IteratorT &first, IteratorT const &last, ContainerT &queue)
{
using namespace cpplexer;
queue.push_back (*first); // queue up the current token
token_id id = next_token<IteratorT>::peek(first, last, false);
if (IS_CATEGORY(id, WhiteSpaceTokenType)) {
do {
queue.push_back(*++first); // queue up the next whitespace
id = next_token<IteratorT>::peek(first, last, false);
} while (IS_CATEGORY(id, WhiteSpaceTokenType));
}
++first;
return id;
}
///////////////////////////////////////////////////////////////////////////////
} // namespace impl
///////////////////////////////////////////////////////////////////////////////
} // namespace util
} // namespace wave
#endif // !defined(UNPUT_QUEUE_ITERATOR_HPP_76DA23D0_4893_4AD5_ABCC_6CED7CFB89BC_INCLUDED)
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