Boost C++ Libraries

Description

BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED and BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED_NS are macros that can be used to generate all the necessary boilerplate to make an arbitrary struct a model of Random Access Sequence and Associative Sequence. The given struct is adapted using the given name.

Synopsis

BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED(
    struct_name, adapted_name,
    ([member_type0,] member_name0, key_type0)
    ([member_type1,] member_name1, key_type1)
    ...
    )

BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED_NS(
    struct_name,
    (namespace0)(namespace1)...,
    adapted_name,
    ([member_type0,] member_name0, key_type0)
    ([member_type1,] member_name1, key_type1)
    ...
    )

Semantics

The above macros generate the necessary code to adapt struct_name as a model of Random Access Sequence and Associative Sequence while using adapted_name as the name of the adapted struct. The sequence (namespace0)(namespace1)... declares the namespace for adapted_name. It yields to a fully qualified name for adapted_name of namespace0::namespace1::... adapted_name. If an empty namespace sequence is given (that is a macro that expands to nothing), the adapted view is placed in the global namespace. If no namespace sequence is given (i.e. BOOST_FUSION_ADAPT_STRUCT_ASSOC_NAMED), the adapted view is placed in the namespace boost::fusion::adapted. The sequence of (member_typeN, member_nameN, key_typeN) triples declares the type, name and key type of each of the struct members that are part of the sequence.

When member_typeN is omitted or set to auto, the type is infered with Boost.TypeOf.

The macros should be used at global scope, and struct_name should be the fully namespace qualified name of the struct to be converted.

Header

#include <boost/fusion/adapted/struct/adapt_assoc_struct_named.hpp>
#include <boost/fusion/include/adapt_assoc_struct_named.hpp>

Example

namespace demo
{
    struct employee
    {
        std::string name;
        int age;
    };
}

namespace keys
{
    struct name;
    struct age;
}

// boost::fusion::adapted::adapted_employee is now a Fusion sequence
// referring to demo::employee
BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED(
    demo::employee, adapted_employee,
    (name, keys::name)
    (age, keys::age))

// Without BOOST_PP_VARIADICS support :
BOOST_FUSION_ADAPT_ASSOC_STRUCT_NAMED(
    demo::employee, adapted_employee,
    (auto, name, keys::name)
    (auto, age, keys::age))