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merge from trunk

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[SVN r56179]
This commit is contained in:
Joel de Guzman
2009-09-14 07:47:53 +00:00
parent 2f8b91828b
commit 2e805be6df
281 changed files with 9335 additions and 11649 deletions
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59
example/cookbook/do_the_bind.cpp
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@ -22,23 +22,29 @@
form.
==============================================================================*/
#include <boost/fusion/functional/invocation/invoke.hpp>
#include <boost/fusion/functional/adapter/unfused_generic.hpp>
#include <boost/fusion/functional/adapter/unfused_rvalue_args.hpp>
#include <boost/fusion/functional/adapter/unfused.hpp>
#include <boost/fusion/support/deduce_sequence.hpp>
#include <boost/fusion/sequence/intrinsic/at.hpp>
#include <boost/fusion/mpl.hpp>
#include <boost/fusion/sequence/intrinsic/front.hpp>
#include <boost/fusion/sequence/intrinsic/empty.hpp>
#include <boost/fusion/sequence/intrinsic/size.hpp>
#include <boost/fusion/algorithm/transformation/transform.hpp>
#include <boost/fusion/algorithm/transformation/pop_front.hpp>
#include <boost/fusion/algorithm/iteration/fold.hpp>
#include <boost/fusion/view/filter_view.hpp>
#include <boost/functional/forward_adapter.hpp>
#include <boost/functional/lightweight_forward_adapter.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/mpl/int.hpp>
#include <boost/mpl/max.hpp>
#include <boost/mpl/next.hpp>
#include <boost/ref.hpp>
#include <iostream>
@ -105,6 +111,7 @@ namespace impl
// returned by bind
template <class BindArgs> class fused_bound_function
{
// Transform arguments to be held by value
typedef typename traits::deduce_sequence<BindArgs>::type bound_args;
bound_args fsq_bind_args;
@ -144,19 +151,40 @@ namespace impl
};
// Find the number of placeholders in use
struct n_placeholders
{
struct fold_op
{
template <typename Sig> struct result;
template <class S, class A, class B> struct result< S(A &,B &) >
: mpl::max<A,B> { };
};
struct filter_pred
{
template <class X> struct apply : is_placeholder<X> { };
};
template <typename Seq>
struct apply
: mpl::next< typename result_of::fold<
fusion::filter_view<Seq,filter_pred>, mpl::int_<-1>, fold_op
>::type>::type
{ };
};
// Fused implementation of the 'bind' function
struct fused_binder
{
template <class Signature>
struct result;
template <class BindArgs>
template <class BindArgs,
int Placeholders = n_placeholders::apply<BindArgs>::value>
struct result_impl
{
// We have to transform the arguments so they are held by-value
// in the returned function.
typedef fusion::unfused_generic<
fused_bound_function<BindArgs> > type;
typedef boost::forward_adapter<fusion::unfused<
fused_bound_function<BindArgs>,!Placeholders>,Placeholders> type;
};
template <class Self, class BindArgs>
@ -168,14 +196,16 @@ namespace impl
inline typename result_impl< BindArgs >::type
operator()(BindArgs & bind_args) const
{
return typename result< void(BindArgs) >::type(bind_args);
return typename result< void(BindArgs) >::type(
fusion::unfused< fused_bound_function<BindArgs>,
! n_placeholders::apply<BindArgs>::value >(bind_args) );
}
};
// The binder's unfused type. We use unfused_rvalue_args to make that
// thing more similar to Boost.Bind. Because of that we have to use
// The binder's unfused type. We use lightweght_forward_adapter to make
// that thing more similar to Boost.Bind. Because of that we have to use
// Boost.Ref (below in the sample code)
typedef fusion::unfused_rvalue_args<fused_binder> binder;
typedef boost::lightweight_forward_adapter< fusion::unfused<fused_binder> > binder;
}
// Placeholder globals
@ -225,10 +255,11 @@ int main()
using boost::ref;
int errors = 0;
errors += !( bind(f)() == 0);
errors += !( bind(f,"Hi")() == 1);
errors += !( bind(f,_1_)("there.") == 1);
errors += !( bind(f,"The answer is",_1_)(value) == 2);
errors += !( bind(f,"The answer is",_1_)(12) == 2);
errors += !( bind(f,_1_,ref(value))("Really?") == 2);
errors += !( bind(f,_1_,_2_)("Dunno. If there is an answer, it's",value) == 2);