/*=============================================================================
    Phoenix V1.0
    Copyright (c) 2001-2003 Joel de Guzman

    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.
==============================================================================*/
#include <vector>
#include <algorithm>
#include <iostream>

#define PHOENIX_LIMIT 5
#include "boost/spirit/phoenix/operators.hpp"
#include "boost/spirit/phoenix/primitives.hpp"
#include "boost/spirit/phoenix/composite.hpp"
#include "boost/spirit/phoenix/special_ops.hpp"
#include "boost/spirit/phoenix/statements.hpp"

namespace phoenix {

///////////////////////////////////////////////////////////////////////////////
//
//  local_tuple
//
//      This *is a* tuple like the one we see in TupleT in any actor
//      base class' eval member function. local_tuple should look and
//      feel the same as a tupled-args, that's why it is derived from
//      TupleArgsT. It has an added member, locs which is another tuple
//      where the local variables will be stored. locs is mutable to
//      allow read-write access to our locals regardless of
//      local_tuple's constness (The eval member function accepts it as
//      a const argument).
//
///////////////////////////////////////////////////////////////////////////////
template <typename TupleArgsT, typename TupleLocsT>
struct local_tuple : public TupleArgsT {

    typedef TupleLocsT local_vars_t;

    local_tuple(TupleArgsT const& args, TupleLocsT const& locs_)
    :   TupleArgsT(args), locs(locs_) {}

    mutable TupleLocsT locs;
};

///////////////////////////////////////////////////////////////////////////////
//
//  local_var_result
//
//      This is a return type computer. Given a constant integer N and a
//      tuple, get the Nth local variable type. If TupleT is not really
//      a local_tuple, we just return nil_t. Otherwise we get the Nth
//      local variable type.
//
///////////////////////////////////////////////////////////////////////////////
template <int N, typename TupleT>
struct local_var_result {

    typedef nil_t type;
};

//////////////////////////////////
template <int N, typename TupleArgsT, typename TupleLocsT>
struct local_var_result<N, local_tuple<TupleArgsT, TupleLocsT> > {

    typedef typename tuple_element<N, TupleLocsT>::type& type;
};

///////////////////////////////////////////////////////////////////////////////
//
//  local_var
//
//      This class looks so curiously like the argument class. local_var
//      provides access to the Nth local variable packed in the tuple
//      duo local_tuple above. Note that the member function eval
//      expects a local_tuple argument. Otherwise the expression
//      'tuple.locs' will fail (compile-time error). local_var
//      primitives only work within the context of a locals_composite
//      (see below).
//
//      Provided are some predefined local_var actors for 0..N local
//      variable access: loc1..locN.
//
///////////////////////////////////////////////////////////////////////////////
template <int N>
struct local_var {

    template <typename TupleT>
    struct result {

        typedef typename local_var_result<N, TupleT>::type type;
    };

    template <typename TupleT>
    typename local_var_result<N, TupleT>::type
    eval(TupleT const& tuple) const
    {
        return tuple.locs[tuple_index<N>()];
    }
};

//////////////////////////////////
actor<local_var<0> > const loc1 = local_var<0>();
actor<local_var<1> > const loc2 = local_var<1>();
actor<local_var<2> > const loc3 = local_var<2>();
actor<local_var<3> > const loc4 = local_var<3>();
actor<local_var<4> > const loc5 = local_var<4>();

///////////////////////////////////////////////////////////////////////////////
//
//  locals_composite
//
//      This class encapsulates an actor and some local variable
//      initializers packed in a tuple.
//
//      locals_composite is just like a proxy and delegates the actual
//      evaluation to the actor. The actor does the actual work. In the
//      eval member function, before invoking the embedded actor's eval
//      member function, we first stuff an instance of our locals and
//      bundle both 'args' and 'locals' in a local_tuple. This
//      local_tuple instance is created in the stack initializing it
//      with our locals member. We then pass this local_tuple instance
//      as an argument to the actor's eval member function.
//
///////////////////////////////////////////////////////////////////////////////
template <typename ActorT, typename LocsT>
struct locals_composite {

    typedef locals_composite<ActorT, LocsT> self_t;

    template <typename TupleT>
    struct result { typedef typename actor_result<ActorT, TupleT>::type type; };

    locals_composite(ActorT const& actor_, LocsT const& locals_)
    :   actor(actor_), locals(locals_) {}

    template <typename TupleT>
    typename actor_result<ActorT, TupleT>::type
    eval(TupleT const& args) const
    {
        actor.eval(local_tuple<TupleT, LocsT>(args, locals));
    }

    ActorT actor;
    LocsT locals;
};

///////////////////////////////////////////////////////////////////////////////
//
//  locals_gen
//
//      At construction time, this class is given some local var-
//      initializers packed in a tuple. We just store this for later.
//      The operator[] of this class creates the actual locals_composite
//      given an actor. This is responsible for the construct
//      locals<types>[actor].
//
///////////////////////////////////////////////////////////////////////////////
template <typename LocsT>
struct locals_gen {

    locals_gen(LocsT const& locals_)
    :   locals(locals_) {}

    template <typename ActorT>
    actor<locals_composite<typename as_actor<ActorT>::type, LocsT> >
    operator[](ActorT const& actor)
    {
        return locals_composite<typename as_actor<ActorT>::type, LocsT>
            (as_actor<ActorT>::convert(actor), locals);
    }

    LocsT locals;
};

///////////////////////////////////////////////////////////////////////////////
//
//    Front end generator functions. These generators are overloaded for
//    1..N local variables. locals<T0,... TN>(i0,...iN) generate locals_gen
//    objects (see above).
//
///////////////////////////////////////////////////////////////////////////////
template <typename T0>
inline locals_gen<tuple<T0> >
locals(
    T0 const& _0 = T0()
)
{
    typedef tuple<T0> tuple_t;
    return locals_gen<tuple_t>(tuple_t(_0));
}

//////////////////////////////////
template <typename T0, typename T1>
inline locals_gen<tuple<T0, T1> >
locals(
    T0 const& _0 = T0(),
    T1 const& _1 = T1()
)
{
    typedef tuple<T0, T1> tuple_t;
    return locals_gen<tuple_t>(tuple_t(_0, _1));
}

//////////////////////////////////
template <typename T0, typename T1, typename T2>
inline locals_gen<tuple<T0, T1, T2> >
locals(
    T0 const& _0 = T0(),
    T1 const& _1 = T1(),
    T2 const& _2 = T2()
)
{
    typedef tuple<T0, T1, T2> tuple_t;
    return locals_gen<tuple_t>(tuple_t(_0, _1, _2));
}

//////////////////////////////////
template <typename T0, typename T1, typename T2, typename T3>
inline locals_gen<tuple<T0, T1, T2, T3> >
locals(
    T0 const& _0 = T0(),
    T1 const& _1 = T1(),
    T2 const& _2 = T2(),
    T3 const& _3 = T3()
)
{
    typedef tuple<T0, T1, T2, T3> tuple_t;
    return locals_gen<tuple_t>(tuple_t(_0, _1, _2, _3));
}

//////////////////////////////////
template <typename T0, typename T1, typename T2, typename T3, typename T4>
inline locals_gen<tuple<T0, T1, T2, T3, T4> >
locals(
    T0 const& _0 = T0(),
    T1 const& _1 = T1(),
    T2 const& _2 = T2(),
    T3 const& _3 = T3(),
    T4 const& _4 = T4()
)
{
    typedef tuple<T0, T1, T2, T3> tuple_t;
    return locals_gen<tuple_t>(tuple_t(_0, _1, _2, _3, _4));
}

///////////////////////////////////////////////////////////////////////////////
}

//////////////////////////////////
using namespace std;
using namespace phoenix;

//////////////////////////////////
int
main()
{
    int init[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
    vector<int> c(init, init + 10);
    typedef vector<int>::iterator iterator;

    for_each(c.begin(), c.end(),
        locals<int, char const*>(0, "...That's all\n")
        [
            for_(loc1 = 0, loc1 < arg1, ++loc1)
            [
                cout << loc1 << ", "
            ],
            cout << loc2
        ]
    );

    return 0;
}
