lyx_mirror/boost/boost/token_iterator.hpp
Lars Gullik Bjønnes 59b6a4701a major boost update
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@4179 a592a061-630c-0410-9148-cb99ea01b6c8
2002-05-21 23:39:58 +00:00

117 lines
4.0 KiB
C++

// Boost token_iterator.hpp -------------------------------------------------//
// Copyright John R. Bandela 2001
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all
// copies. This software is provided "as is" without express or
// implied warranty, and with no claim as to its suitability for any
// purpose.
// See http://www.boost.org for updates, documentation, and revision history.
#ifndef BOOST_TOKENIZER_POLICY_JRB051801_HPP_
#define BOOST_TOKENIZER_POLICY_JRB051801_HPP_
#include<boost/iterator_adaptors.hpp>
#include<boost/token_functions.hpp>
#include<utility>
#include<cassert>
namespace boost {
namespace detail{
// The base "iterator" for iterator adapter
template<class It>
class token_iterator_base
{
public:
std::pair<It,It> p_;
bool valid_;
token_iterator_base():p_(It(),It()),valid_(false){}
token_iterator_base(const It& b , const It& e )
:p_(b,e),valid_(false){}
operator It(){return p_.first;}
template<class T>
token_iterator_base(const token_iterator_base<T>& other)
:p_(other.p_),valid_(other.valid_){}
};
template<class Type, class TokenizerFunc>
class tokenizer_policy{
private:
TokenizerFunc func_;
Type tok_;
public:
tokenizer_policy(){}
tokenizer_policy(const TokenizerFunc& f):func_(f){};
template<class Base>
void initialize(Base& b){
if(b.valid_) return;
func_.reset();
b.valid_ = (b.p_.first != b.p_.second)?
func_(b.p_.first,b.p_.second,tok_):false;
}
template<class Iterator1, class Iterator2>
bool equal(const Iterator1& a, const Iterator2& b) const{
return (a.base().valid_ && b.base().valid_)
?(a.base().p_==b.base().p_)
:(a.base().valid_==b.base().valid_);
}
template<class Iterator>
typename Iterator::reference
dereference(const Iterator& a) const{
using namespace std;
assert(a.base().valid_);
return tok_;
}
template <class Iterator>
void increment(Iterator& b){
using namespace std;
assert(b.base().valid_);
b.base().valid_ = func_(b.base().p_.first,b.base().p_.second,tok_);
}
};
} // namespace detail
template <
class TokenizerFunc = char_delimiters_separator<char>,
class Iterator = std::string::const_iterator,
class Type = std::string
>
class token_iterator_generator {
private:
typedef Type value_type;
typedef detail::tokenizer_policy<Type, TokenizerFunc> policies;
typedef detail::token_iterator_base<Iterator> base;
typedef typename boost::detail::non_bidirectional_category<
Iterator>::type category;
public:
typedef boost::iterator_adaptor<base,policies,value_type,
const value_type&,const value_type*,category,std::ptrdiff_t> type;
};
// Type has to be first because it needs to be explicitly specified
// because there is no way the function can deduce it.
template<class Type, class Iterator, class TokenizerFunc>
typename token_iterator_generator<TokenizerFunc,Iterator,Type>::type
make_token_iterator(Iterator begin, Iterator end,const TokenizerFunc& fun){
typedef typename
token_iterator_generator<TokenizerFunc,Iterator,Type>::type ret_type;
detail::token_iterator_base<Iterator> b(begin,end);
detail::tokenizer_policy<Type,TokenizerFunc> f(fun);
return ret_type(b,f);
}
} // namespace boost
#endif