classification.hpp

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//  Boost string_algo library classification.hpp header file  ---------------------------//

//  Copyright Pavol Droba 2002-2003.
//
// 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/ for updates, documentation, and revision history.

#ifndef BOOST_STRING_CLASSIFICATION_HPP
#define BOOST_STRING_CLASSIFICATION_HPP

#include <algorithm>
#include <locale>
#include <boost/range/value_type.hpp>
#include <boost/range/as_literal.hpp>
#include <boost/algorithm/string/detail/classification.hpp>
#include <boost/algorithm/string/predicate_facade.hpp>


/*! \file
    Classification predicates are included in the library to give 
    some more convenience when using algorithms like \c trim() and \c all(). 
    They wrap functionality of STL classification functions ( e.g. \c std::isspace() )
    into generic functors. 
*/

namespace boost {
    namespace algorithm {

//  classification functor generator -------------------------------------//

        //! is_classified predicate
        /*!
            Construct the \c is_classified predicate. This predicate holds if the input is
            of specified \c std::ctype category.

            \param Type A \c std::ctype category
            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF
        is_classified(std::ctype_base::mask Type, const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(Type, Loc);
        }

        //! is_space predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::space category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate
        */
        inline detail::is_classifiedF 
        is_space(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::space, Loc);
        }

        //! is_alnum predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::alnum category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_alnum(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::alnum, Loc);
        }

        //! is_alpha predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::alpha category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_alpha(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::alpha, Loc);
        }

        //! is_cntrl predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::cntrl category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_cntrl(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::cntrl, Loc);
        }

        //! is_digit predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::digit category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_digit(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::digit, Loc);
        }

        //! is_graph predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::graph category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF
        is_graph(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::graph, Loc);
        }

        //! is_lower predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::lower category.   

            \param Loc A locale used for classification
            \return An instance of \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_lower(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::lower, Loc);
        }

        //! is_print predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::print category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_print(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::print, Loc);
        }

        //! is_punct predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::punct category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_punct(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::punct, Loc);
        }

        //! is_upper predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::upper category.   

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_upper(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::upper, Loc);
        }

        //! is_xdigit predicate
        /*!
            Construct the \c is_classified predicate for the \c ctype_base::xdigit category.  

            \param Loc A locale used for classification
            \return An instance of the \c is_classified predicate 
        */
        inline detail::is_classifiedF 
        is_xdigit(const std::locale& Loc=std::locale())
        {
            return detail::is_classifiedF(std::ctype_base::xdigit, Loc);
        }

        //! is_any_of predicate
        /*!
            Construct the \c is_any_of predicate. The predicate holds if the input
            is included in the specified set of characters.

            \param Set A set of characters to be recognized
            \return An instance of the \c is_any_of predicate 
        */
        template<typename RangeT>
        inline detail::is_any_ofF<
            BOOST_STRING_TYPENAME range_value<RangeT>::type> 
        is_any_of( const RangeT& Set )
        {
            iterator_range<BOOST_STRING_TYPENAME range_const_iterator<RangeT>::type> lit_set(as_literal(Set));
            return detail::is_any_ofF<BOOST_STRING_TYPENAME range_value<RangeT>::type>(lit_set); 
        }

        //! is_from_range predicate
        /*!
            Construct the \c is_from_range predicate. The predicate holds if the input
            is included in the specified range. (i.e. From <= Ch <= To )

            \param From The start of the range
            \param To The end of the range
            \return An instance of the \c is_from_range predicate 
        */
        template<typename CharT>
        inline detail::is_from_rangeF<CharT> is_from_range(CharT From, CharT To)
        {
            return detail::is_from_rangeF<CharT>(From,To); 
        }
        
        // predicate combinators ---------------------------------------------------//

        //! predicate 'and' composition predicate
        /*!
            Construct the \c class_and predicate. This predicate can be used
            to logically combine two classification predicates. \c class_and holds,
            if both predicates return true.

            \param Pred1 The first predicate
            \param Pred2 The second predicate
            \return An instance of the \c class_and predicate     
        */
        template<typename Pred1T, typename Pred2T>
        inline detail::pred_andF<Pred1T, Pred2T>
        operator&&( 
            const predicate_facade<Pred1T>& Pred1, 
            const predicate_facade<Pred2T>& Pred2 )
        {    
            // Doing the static_cast with the pointer instead of the reference
            // is a workaround for some compilers which have problems with
            // static_cast's of template references, i.e. CW8. /grafik/
            return detail::pred_andF<Pred1T,Pred2T>(
                *static_cast<const Pred1T*>(&Pred1), 
                *static_cast<const Pred2T*>(&Pred2) );
        }

        //! predicate 'or' composition predicate
        /*!
            Construct the \c class_or predicate. This predicate can be used
            to logically combine two classification predicates. \c class_or holds,
            if one of the predicates return true.

            \param Pred1 The first predicate
            \param Pred2 The second predicate
            \return An instance of the \c class_or predicate     
        */
        template<typename Pred1T, typename Pred2T>
        inline detail::pred_orF<Pred1T, Pred2T>
        operator||( 
            const predicate_facade<Pred1T>& Pred1, 
            const predicate_facade<Pred2T>& Pred2 )
        {    
            // Doing the static_cast with the pointer instead of the reference
            // is a workaround for some compilers which have problems with
            // static_cast's of template references, i.e. CW8. /grafik/
            return detail::pred_orF<Pred1T,Pred2T>(
                *static_cast<const Pred1T*>(&Pred1), 
                *static_cast<const Pred2T*>(&Pred2));
        }

        //! predicate negation operator
        /*!
            Construct the \c class_not predicate. This predicate represents a negation. 
            \c class_or holds if of the predicates return false.

            \param Pred The predicate to be negated
            \return An instance of the \c class_not predicate     
        */
        template<typename PredT>
        inline detail::pred_notF<PredT>
        operator!( const predicate_facade<PredT>& Pred )
        {
            // Doing the static_cast with the pointer instead of the reference
            // is a workaround for some compilers which have problems with
            // static_cast's of template references, i.e. CW8. /grafik/
            return detail::pred_notF<PredT>(*static_cast<const PredT*>(&Pred)); 
        }

    } // namespace algorithm

    // pull names to the boost namespace
    using algorithm::is_classified;
    using algorithm::is_space;
    using algorithm::is_alnum;
    using algorithm::is_alpha;
    using algorithm::is_cntrl;
    using algorithm::is_digit;
    using algorithm::is_graph;
    using algorithm::is_lower;
    using algorithm::is_upper;
    using algorithm::is_print;
    using algorithm::is_punct;
    using algorithm::is_xdigit;
    using algorithm::is_any_of;
    using algorithm::is_from_range;

} // namespace boost

#endif  // BOOST_STRING_PREDICATE_HPP