// Copyright (c) 2001-2011 Hartmut Kaiser | |
// | |
// 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) | |
#if !defined(BOOST_SPIRIT_KARMA_CENTER_ALIGNMENT_FEB_27_2007_1216PM) | |
#define BOOST_SPIRIT_KARMA_CENTER_ALIGNMENT_FEB_27_2007_1216PM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/karma/meta_compiler.hpp> | |
#include <boost/spirit/home/karma/generator.hpp> | |
#include <boost/spirit/home/karma/domain.hpp> | |
#include <boost/spirit/home/karma/detail/output_iterator.hpp> | |
#include <boost/spirit/home/karma/detail/default_width.hpp> | |
#include <boost/spirit/home/karma/delimit_out.hpp> | |
#include <boost/spirit/home/karma/auxiliary/lazy.hpp> | |
#include <boost/spirit/home/support/unused.hpp> | |
#include <boost/spirit/home/support/common_terminals.hpp> | |
#include <boost/spirit/home/support/has_semantic_action.hpp> | |
#include <boost/spirit/home/support/handles_container.hpp> | |
#include <boost/spirit/home/karma/detail/attributes.hpp> | |
#include <boost/spirit/home/support/info.hpp> | |
#include <boost/spirit/home/support/unused.hpp> | |
#include <boost/fusion/include/at.hpp> | |
#include <boost/fusion/include/vector.hpp> | |
#include <boost/lexical_cast.hpp> | |
#include <boost/integer_traits.hpp> | |
#include <boost/mpl/bool.hpp> | |
#include <boost/utility/enable_if.hpp> | |
#include <boost/detail/workaround.hpp> | |
/////////////////////////////////////////////////////////////////////////////// | |
namespace boost { namespace spirit | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// Enablers | |
/////////////////////////////////////////////////////////////////////////// | |
// enables center[] | |
template <> | |
struct use_directive<karma::domain, tag::center> | |
: mpl::true_ {}; | |
// enables center(d)[g] and center(w)[g], where d is a generator | |
// and w is a maximum width | |
template <typename T> | |
struct use_directive<karma::domain | |
, terminal_ex<tag::center, fusion::vector1<T> > > | |
: mpl::true_ {}; | |
// enables *lazy* delimit(d)[g], where d provides a generator | |
template <> | |
struct use_lazy_directive<karma::domain, tag::center, 1> | |
: mpl::true_ {}; | |
// enables center(w, d)[g], where d is a generator and w is a maximum | |
// width | |
template <typename Width, typename Padding> | |
struct use_directive<karma::domain | |
, terminal_ex<tag::center, fusion::vector2<Width, Padding> > > | |
: spirit::traits::matches<karma::domain, Padding> {}; | |
// enables *lazy* delimit(w, d)[g], where d provides a generator and w is | |
// a maximum width | |
template <> | |
struct use_lazy_directive<karma::domain, tag::center, 2> | |
: mpl::true_ {}; | |
}} | |
/////////////////////////////////////////////////////////////////////////////// | |
namespace boost { namespace spirit { namespace karma | |
{ | |
using spirit::center; | |
using spirit::center_type; | |
namespace detail | |
{ | |
/////////////////////////////////////////////////////////////////////// | |
// The center_generate template function is used for all the | |
// different flavors of the center[] directive. | |
/////////////////////////////////////////////////////////////////////// | |
template <typename OutputIterator, typename Context, typename Delimiter, | |
typename Attribute, typename Embedded, typename Padding> | |
inline static bool | |
center_generate(OutputIterator& sink, Context& ctx, | |
Delimiter const& d, Attribute const& attr, Embedded const& e, | |
unsigned int const width, Padding const& p) | |
{ | |
#if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1600)) | |
e; // suppresses warning: C4100: 'e' : unreferenced formal parameter | |
#endif | |
// wrap the given output iterator to allow left padding | |
detail::enable_buffering<OutputIterator> buffering(sink, width); | |
bool r = false; | |
// first generate the embedded output | |
{ | |
detail::disable_counting<OutputIterator> nocounting(sink); | |
r = e.generate(sink, ctx, d, attr); | |
} // re-enable counting | |
buffering.disable(); // do not perform buffering any more | |
// generate the left padding | |
detail::enable_counting<OutputIterator> counting(sink); | |
std::size_t const pre = width - (buffering.buffer_size() + width)/2; | |
while (r && counting.count() < pre) | |
r = p.generate(sink, ctx, unused, unused); | |
if (r) { | |
// copy the embedded output to the target output iterator | |
buffering.buffer_copy(); | |
// generate the right padding | |
while (r && counting.count() < width) | |
r = p.generate(sink, ctx, unused, unused); | |
} | |
return r; | |
} | |
} | |
/////////////////////////////////////////////////////////////////////////// | |
// The simple left alignment directive is used for center[...] | |
// generators. It uses default values for the generated width (defined via | |
// the BOOST_KARMA_DEFAULT_FIELD_LENGTH constant) and for the padding | |
// generator (always spaces). | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Width = detail::default_width> | |
struct simple_center_alignment | |
: unary_generator<simple_center_alignment<Subject, Width> > | |
{ | |
typedef Subject subject_type; | |
typedef mpl::int_< | |
generator_properties::countingbuffer | subject_type::properties::value | |
> properties; | |
template <typename Context, typename Iterator> | |
struct attribute | |
: traits::attribute_of<subject_type, Context, Iterator> | |
{}; | |
simple_center_alignment(Subject const& subject, Width width = Width()) | |
: subject(subject), width(width) {} | |
template <typename OutputIterator, typename Context, typename Delimiter | |
, typename Attribute> | |
bool generate(OutputIterator& sink, Context& ctx, Delimiter const& d | |
, Attribute const& attr) const | |
{ | |
return detail::center_generate(sink, ctx, d, attr, | |
subject, width, compile<karma::domain>(' ')); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
return info("center", subject.what(context)); | |
} | |
Subject subject; | |
Width width; | |
}; | |
/////////////////////////////////////////////////////////////////////////// | |
// The left alignment directive with padding, is used for generators like | |
// center(padding)[...], where padding is a arbitrary generator | |
// expression. It uses a default value for the generated width (defined | |
// via the BOOST_KARMA_DEFAULT_FIELD_LENGTH constant). | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Padding | |
, typename Width = detail::default_width> | |
struct padding_center_alignment | |
: unary_generator<padding_center_alignment<Subject, Padding, Width> > | |
{ | |
typedef Subject subject_type; | |
typedef Padding padding_type; | |
typedef mpl::int_< | |
generator_properties::countingbuffer | | |
subject_type::properties::value | padding_type::properties::value | |
> properties; | |
template <typename Context, typename Iterator> | |
struct attribute | |
: traits::attribute_of<Subject, Context, Iterator>::type | |
{}; | |
padding_center_alignment(Subject const& subject, Padding const& padding | |
, Width width = Width()) | |
: subject(subject), padding(padding), width(width) {} | |
template <typename OutputIterator, typename Context, typename Delimiter | |
, typename Attribute> | |
bool generate(OutputIterator& sink, Context& ctx, Delimiter const& d | |
, Attribute const& attr) const | |
{ | |
return detail::center_generate(sink, ctx, d, attr, | |
subject, width, padding); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
return info("center", subject.what(context)); | |
} | |
Subject subject; | |
Padding padding; | |
Width width; | |
}; | |
/////////////////////////////////////////////////////////////////////////// | |
// Generator generators: make_xxx function (objects) | |
/////////////////////////////////////////////////////////////////////////// | |
// creates center[] directive generator | |
template <typename Subject, typename Modifiers> | |
struct make_directive<tag::center, Subject, Modifiers> | |
{ | |
typedef simple_center_alignment<Subject> result_type; | |
result_type operator()(unused_type, Subject const& subject | |
, unused_type) const | |
{ | |
return result_type(subject); | |
} | |
}; | |
// creates center(width)[] directive generator | |
template <typename Width, typename Subject, typename Modifiers> | |
struct make_directive< | |
terminal_ex<tag::center, fusion::vector1<Width> > | |
, Subject, Modifiers | |
, typename enable_if_c< integer_traits<Width>::is_integral >::type> | |
{ | |
typedef simple_center_alignment<Subject, Width> result_type; | |
template <typename Terminal> | |
result_type operator()(Terminal const& term, Subject const& subject | |
, unused_type) const | |
{ | |
return result_type(subject, fusion::at_c<0>(term.args)); | |
} | |
}; | |
// creates center(pad)[] directive generator | |
template <typename Padding, typename Subject, typename Modifiers> | |
struct make_directive< | |
terminal_ex<tag::center, fusion::vector1<Padding> > | |
, Subject, Modifiers | |
, typename enable_if< | |
mpl::and_< | |
spirit::traits::matches<karma::domain, Padding>, | |
mpl::not_<mpl::bool_<integer_traits<Padding>::is_integral> > | |
> | |
>::type> | |
{ | |
typedef typename | |
result_of::compile<karma::domain, Padding, Modifiers>::type | |
padding_type; | |
typedef padding_center_alignment<Subject, padding_type> result_type; | |
template <typename Terminal> | |
result_type operator()(Terminal const& term, Subject const& subject | |
, Modifiers const& modifiers) const | |
{ | |
return result_type(subject | |
, compile<karma::domain>(fusion::at_c<0>(term.args), modifiers)); | |
} | |
}; | |
// creates center(width, pad)[] directive generator | |
template <typename Width, typename Padding, typename Subject | |
, typename Modifiers> | |
struct make_directive< | |
terminal_ex<tag::center, fusion::vector2<Width, Padding> > | |
, Subject, Modifiers> | |
{ | |
typedef typename | |
result_of::compile<karma::domain, Padding, Modifiers>::type | |
padding_type; | |
typedef padding_center_alignment<Subject, padding_type, Width> result_type; | |
template <typename Terminal> | |
result_type operator()(Terminal const& term, Subject const& subject | |
, Modifiers const& modifiers) const | |
{ | |
return result_type(subject | |
, compile<karma::domain>(fusion::at_c<1>(term.args), modifiers) | |
, fusion::at_c<0>(term.args)); | |
} | |
}; | |
}}} // namespace boost::spirit::karma | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Width> | |
struct has_semantic_action<karma::simple_center_alignment<Subject, Width> > | |
: unary_has_semantic_action<Subject> {}; | |
template <typename Subject, typename Padding, typename Width> | |
struct has_semantic_action< | |
karma::padding_center_alignment<Subject, Padding, Width> > | |
: unary_has_semantic_action<Subject> {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Subject, typename Width, typename Attribute | |
, typename Context, typename Iterator> | |
struct handles_container< | |
karma::simple_center_alignment<Subject, Width>, Attribute | |
, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
template <typename Subject, typename Padding, typename Width | |
, typename Attribute, typename Context, typename Iterator> | |
struct handles_container< | |
karma::padding_center_alignment<Subject, Padding, Width> | |
, Attribute, Context, Iterator> | |
: unary_handles_container<Subject, Attribute, Context, Iterator> {}; | |
}}} | |
#endif | |