libs/phoenix/doc/modules/object.qbk

[/==============================================================================
    Copyright (C) 2001-2010 Joel de Guzman
    Copyright (C) 2001-2005 Dan Marsden
    Copyright (C) 2001-2010 Thomas Heller

    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)
===============================================================================/]

[def __limit_note__ 
The maximum number of actual parameters is limited by the
preprocessor constant BOOST_PHOENIX_COMPOSITE_LIMIT. Note though, that this limit
should not be greater than BOOST_PHOENIX_LIMIT. By default, `BOOST_PHOENIX_COMPOSITE_LIMIT`
is set to `BOOST_PHOENIX_LIMIT` (See [link phoenix.actor Actor]).
]

[section Object]

The Object module deals with object construction, destruction and conversion.
The module provides /"lazy"/ versions of C++'s object constructor, `new`,
`delete`, `static_cast`, `dynamic_cast`, `const_cast` and `reinterpret_cast`.

[section Construction]

[*/Lazy constructors.../]

    #include <boost/phoenix/object/construct.hpp>

Lazily construct an object from an arbitrary set of arguments:

    construct<T>(ctor_arg1, ctor_arg2, ..., ctor_argN);

where the given parameters are the parameters to the constructor of the object of
type T (This implies, that type T is expected to have a constructor with a
corresponding set of parameter types.).

Example:

    construct<std::string>(arg1, arg2)

Constructs a `std::string` from `arg1` and `arg2`.

[note __limit_note__ ]

[endsect]
[section New]

[*/Lazy new.../]

    #include <boost/phoenix/object/new.hpp>

Lazily construct an object, on the heap, from an arbitrary set of arguments:

    new_<T>(ctor_arg1, ctor_arg2, ..., ctor_argN);

where the given parameters are the parameters to the contractor of the object of
type T (This implies, that type T is expected to have a constructor with a
corresponding set of parameter types.).

Example:

    new_<std::string>(arg1, arg2) // note the spelling of new_ (with trailing underscore)

Creates a `std::string` from `arg1` and `arg2` on the heap.

[note __limit_note__ ]

[endsect]
[section Delete]

[*/Lazy delete.../]

    #include <boost/phoenix/object/delete.hpp>

Lazily delete an object, from the heap:

    delete_(arg);

where arg is assumed to be a pointer to an object.

Example:

    delete_<std::string>(arg1) // note the spelling of delete_ (with trailing underscore)

[endsect]
[section Casts]

[*/Lazy casts.../]

    #include <boost/phoenix/object/static_cast.hpp>
    #include <boost/phoenix/object/dynamic_cast.hpp>
    #include <boost/phoenix/object/const_cast.hpp>
    #include <boost/phoenix/object/reinterpret_cast.hpp>

The set of lazy C++ cast template functions provide a way of lazily casting an
object of a certain type to another type. The syntax resembles the well known
C++ casts. Take note however that the lazy versions have a trailing underscore.

    static_cast_<T>(lambda_expression)
    dynamic_cast_<T>(lambda_expression)
    const_cast_<T>(lambda_expression)
    reinterpret_cast_<T>(lambda_expression)

Example:

    static_cast_<Base*>(&arg1)

Static-casts the address of `arg1` to a `Base*`.

[endsect]

[endsect]