WSJT-X/boost/boost/token_iterator.hpp

129 lines
3.6 KiB
C++

// Boost token_iterator.hpp -------------------------------------------------//
// Copyright John R. Bandela 2001
// Distributed under 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 http://www.boost.org/libs/tokenizer for documentation.
// Revision History:
// 16 Jul 2003 John Bandela
// Allowed conversions from convertible base iterators
// 03 Jul 2003 John Bandela
// Converted to new iterator adapter
#ifndef BOOST_TOKENIZER_POLICY_JRB070303_HPP_
#define BOOST_TOKENIZER_POLICY_JRB070303_HPP_
#include <boost/assert.hpp>
#include <boost/iterator/iterator_adaptor.hpp>
#include <boost/iterator/minimum_category.hpp>
#include <boost/token_functions.hpp>
#include <utility>
namespace boost
{
template <class TokenizerFunc, class Iterator, class Type>
class token_iterator
: public iterator_facade<
token_iterator<TokenizerFunc, Iterator, Type>
, Type
, typename iterators::minimum_category<
forward_traversal_tag
, typename iterator_traversal<Iterator>::type
>::type
, const Type&
>
{
friend class iterator_core_access;
TokenizerFunc f_;
Iterator begin_;
Iterator end_;
bool valid_;
Type tok_;
void increment(){
BOOST_ASSERT(valid_);
valid_ = f_(begin_,end_,tok_);
}
const Type& dereference() const {
BOOST_ASSERT(valid_);
return tok_;
}
template<class Other>
bool equal(const Other& a) const{
return (a.valid_ && valid_)
?( (a.begin_==begin_) && (a.end_ == end_) )
:(a.valid_==valid_);
}
void initialize(){
if(valid_) return;
f_.reset();
valid_ = (begin_ != end_)?
f_(begin_,end_,tok_):false;
}
public:
token_iterator():begin_(),end_(),valid_(false),tok_() { }
token_iterator(TokenizerFunc f, Iterator begin, Iterator e = Iterator())
: f_(f),begin_(begin),end_(e),valid_(false),tok_(){ initialize(); }
token_iterator(Iterator begin, Iterator e = Iterator())
: f_(),begin_(begin),end_(e),valid_(false),tok_() {initialize();}
template<class OtherIter>
token_iterator(
token_iterator<TokenizerFunc, OtherIter,Type> const& t
, typename enable_if_convertible<OtherIter, Iterator>::type* = 0)
: f_(t.tokenizer_function()),begin_(t.base())
,end_(t.end()),valid_(!t.at_end()),tok_(t.current_token()) {}
Iterator base()const{return begin_;}
Iterator end()const{return end_;}
TokenizerFunc tokenizer_function()const{return f_;}
Type current_token()const{return tok_;}
bool at_end()const{return !valid_;}
};
template <
class TokenizerFunc = char_delimiters_separator<char>,
class Iterator = std::string::const_iterator,
class Type = std::string
>
class token_iterator_generator {
private:
public:
typedef token_iterator<TokenizerFunc,Iterator,Type> 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;
return ret_type(fun,begin,end);
}
} // namespace boost
#endif