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Version 90 (modified by viboes, 13 years ago) ( diff )
Added Boost.NumericBindings

Libraries Under Construction
Other Open Source libraries
1. ASL
2. async
3. coco
4. Poet
5. TBB
6. tscb
Libraries Under Discussion
Libraries Wish list
1. Accumulators.Ext
2. Cloner
3. ConstraintsProgramming
4. Database
5. DenseSet
6. Enums
7. EnumSet
8. EnumArray
9. Frames
10. ObjectRole
11. Quartets
12. SpreadSheet
Abandoned
1. Boost.ConceptTraits
Libraries Listed by Category

WARNING: The contents of this page could be incomplete and outdated. Please help us to improve this page by modifying it directly or posting on the Boost mailing lists boost-AT-lists.boost.org or boost-users-AT-lists.boost.org with the prefix `[LibrariesUnderConstruction].

See Boost Releases documentation for the list of libraries Boost by release. See Boost Review Schedule for Boost ongoing details.

Most of the ongoing libraries are stored on the SVN Sandbox, the Boost Vault or on specific sites.

Libraries Under Construction

This page is an index page for libraries under construction.

Boost.Algorithm.Sorting

Author(s): Steven Ross
Version:
State:
Last upload: 2009 Jan 13
Links: Bosst Vault
Categories: Algorithm
Description: The Sorting Algorithm Library provides a generic implementation of high-speed sorting algorithms that outperform those in the C++ standard in both average and worst case performance. These algorithms only work on random access iterators.

These algorithms are hybrids using both radix and comparison-based sorting, specialized to sorting common data types, such as integers, floats, and strings. These algorithms are encoded in a generic fashion and accept functors, enabling them to sort any object that can be processed like these basic data types.

Unlike many radix-based algorithms, the underlying Spreadsort algorithm is designed around worst-case performance, and performs better on chunky data (where it is not widely distributed), so that on real data it can perform substantially better than on random data. Conceptually, Spreadsort can sort any data for which an absolute ordering can be determined.

Boost.AllocPlus

Author(s): Ion Gaztañaga igaztanaga-AT-gmail.com
Version:
State:
Last upload:
Links: Documentation Download
Categories: Memory
Description:Allocators optimizations

Boost.Asio.eos_portable_archive

Author(s): Ion Gaztañaga igaztanaga-AT-gmail.com
Version:
State:
Last upload:
Links: Documentation Download
Categories: Concurrent Programming
Description:portable archive

Boost.Async

Author(s): Vicente J. Botet Escribá
Version: 0.2
State: Quite Stable
Last upload: 2009 May 24
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming Containers
Description: Asynchronous Executors (AE) and Asynchronous Completion Tokens (ACT) in a generic way (or at least this was my intention). The library can be considered as a front-end for several Asynchronous Execution models making it possible to share common algorithms and making easier to switch from an Asynchronous Executors to another.

Next follows the motivation for the library and how the library can manage with this concepts.

In N1833 - Preliminary Threading Library Proposal for TR2 Kevlin Henney introduce the concept of threader and a function thread that evaluate a function asynchronously and returns a joiner handle. In N2185 - Proposed Text for Parallel Task Execution Peter Dimov introduce a fork function able to evaluate a function asynchronously and returns a future handle. In N2276 - Thread Pools and Futures Anthony William introduce launch_in_thread and launch_in_pool function templates which evaluate a function asynchronously either in a specific thread or a thread pool and returns a unique_future handle. In Boost.ThreadPool Oliver Kowalke propose a complete implementation of a thread pool with a submit function which evaluate a function asynchronously and returns a task handle.

Behind all these proposal there is a concept of asynchronous executor, fork-launch-like function and the asynchronous completion token handle.

Name	executor	fork-like	ACT
Boost.Thread	??	thread constructor	thread
Boost.ThreadPool	tp::pool	submit	tp::task
N2276	thread	launch_in_thread	unique_future<T>
N2276	thread_pool	launch_in_pool	unique_future<T>
N2185	??	fork	future<T>
N1833	threader	thread	joiner<T>

The asynchronous completion token models can follows two interfaces, the thread interface and the unique_future interface. Some asynchronous completion token handles allows to recover the result of the evaluation of the function (futures), other allows to manage the underlying thread of execution (thread) and some both (joiner and tp::task).

It seems natural to make a generic fork function that will evaluate a function asynchronously with respect to the calling thread and returns an ACT handle. The following meta-function associated an ACT handle to a asynchronous executor.

template <typename AE, typename T>
struct asynchronous_completion_token {
    typedef typename AE::template handle<T>::type type;
};

The result of forking a nullary function by an asynchronous executor is given by the following meta-function:

namespace result_of { 
    template <typename AE,typename F>
    struct fork {
        typedef typename asynchronous_completion_token<AE, typename result_of<F()>::type>::type type;
    };   
}

The default implementation of fork delegates on fork asynchronous executor function.

template< typename AE, typename F > 
result_of::fork<AE, F>::type fork( AE& ae, F fn ) {
    return ae.fork(fn);
}

Forking n-ary functions relies on the nullary version and bind.

template< typename AE, typename F, typename A1, ..., typename An > 
asynchronous_completion_token<AE, typename result_of<F(A1,..., An)>::type >::type 
fork( AE& ae, F fn, A1 a1, ..., An an ) {
    return ae.fork( bind( fn, a1, ..., an ) );
}

Boost.Async is a C++ library to allow the calling of functions and functors in an asynchronous manner, thereby making it easier to improve the level of concurrency and parallelism in your applications. It provides:

An asynchronous execution framework working with AsynchronousExecutor and AsynchronousCompletionToken. It includes some generic functions and several AsynchronousExecutor and AsynchronousCompletionToken:
- fork and fork_all to execute asynchronously functions
- fork_after: request an AsynchronousExecutor to execute a function asynchronously once each one of AsynchronousCompletionToken in the dependency tuple parameter are ready. It is similar to the async_with_dependencies proposed Peter Dimov.
- generic get, join, ... free functions to synchroyze on an AsynchronousCompletionToken
- generic get_all, join_all, ... free functions to synchroyze on multiple AsynchronousCompletionToken
- generic wait_for_all, wait_for_any to execute asynchronously functions and wait for the completion of all or any of them.
Some AsynchronousExecutor and AsynchronousCompletionToken models
- inmediate executors: executes synchronously a function on the current thread. Often used for test purposes
- basic_threader: can be seen as a thread factory executing asynchronously a function on the returned thread.
- launchers: Lanchers can be seen as a future factory executing asynchronously a function on a hidden thread.
- threader/joiner: A Threader runs a unary function in its own thread. A Threader can be seen as a Joiner factory executing asynchronously a function on a thread encapsulated on the returned Joiner. The joiner is used to synchronize with and pick up the result from a function or to manage the encapsulated thread.
- tp::pool and tp::task customization as an AsynchronousExecutor and an AsynchronousCompletionToken respectively. tp::pool can be seen as a tp::task factory executing asynchronously a function on a pool of threads.
- a generic asynchronous_executor_decorator which allows to decorate the function to be evaluated asynchronously.

Boost.Bitfield

Author(s): Emile Cormier, Vicente J. Botet Escribá
Version: 0.1
State: Stable - Formal review requested - Looking for a review manager
Last upload: 2009 October 15
Links: Boost Vault Boost Sandbox Documentation
Categories: Portability
Description:Portable bitfields traits

a generic bitfield traits class providing generic getter and setter methods.
a BOOST_BITFIELD_DCL macro making easier the definition of the bitfield traits and the bitfield getter and setter functions.

    struct X {
        typedef boost::ubig_32 storage_type;
        storage_type d0;
        typedef unsigned int value_type;
        BOOST_BITFIELD_DCL(storage_type, d0, unsigned int, d00, 0, 10);
        BOOST_BITFIELD_DCL(storage_type, d0, unsigned int, d01, 11, 31);
    };

Boost.BloomFilters

Author(s): Dean Michael Berris
Version: 0.1
State:
Last upload: 2009 June 08
Links: Boost Sandbox
Categories: Containers
Description:Bloo Filters

A Bloom Filter is a space efficient data-structure that allows you to represent set membership that allows for false positives (elements may have been marked as included in a set when they really aren't part of the set) but not false negatives (when an element has not been included/added in the set, the bloom filter wouldn't show that they are part of the set). These have been used in proxy caches to signify whether they already have a cached copy of a URI. File systems also use these to see whether a part of a file (or a page) has already been accessed before (to limit the frequency of fetching pages that have been fetched before on a DFS for instance).

A more in-depth explanation of bloom filters can be found here: http://en.wikipedia.org/wiki/Bloom_filter

Boost.Channel

Author(s): Yigong Liu
Version: 0.4
State: Stable
Last upload:Jul 15, 2008
Links: Web Site Boost Vault
Categories: Distribution
Description: Channel is a C++ framework for distributed message passing and event dispatching, configurable with its components (msg ids,routing algorithms...) as template parameters. As a namespace shared by peer threads, channel supports scope control and filtering.

Boost.Chrono

Author(s): Beman Dawes
Version:
State:
Last upload:2008 Nov 26
Links: Boost Sandbox
Categories: System
Description: The Boost Chrono library provides:
- The C++0x Standard Library's time utilities, including:
  - Class template duration
  - Class template time_point
  - Clocks:
    - system_clock
    - monotonic_clock
    - high_resolution_clock
- Class template timer, with typedefs:
  - system_timer
  - monotonic_timer
  - high_resolution_timer
- Process clocks and timers:
  - process_clock, capturing real, user-CPU, and system-CPU times.
  - process_timer, capturing elapsed real, user-CPU, and system-CPU times.
  - run_timer, convenient reporting of process_timer results.
- The C++0x Standard Library's compile-time rational arithmetic.

Boost.CLI

Author(s): Jean-Daniel Michaud
Version:
State:
Last upload: 2007
Links: Boost Vault
Categories: Input/Output
Description: .

Boost.Cloneable

Author(s): Christian Schladetsch
Version: 0.1
State:
Last upload: 2009 July 08
Links: Boost Sandbox
Categories: Containers Data Structures Utilities
Description: The Boost.Cloneable library provides a means for creating, duplicating, and querying instances of object types that are specified in class hierarchies, and a set of containers for those objects.

Cloneable objects can create clones of derived types from base types, can do so given any STL-compliant allocator, and supports multiple clone type targets.

The user of the library is able to override the default cloning process, and may supply custom allocators. Cloneable types can derive from other cloneable types, in which case the user can specify which subobject type to duplicate or create when making a new clone or new object from an existing instance.

You can use Boost.Cloneable with existing, external types without modification to those types by using the supplied adaptor mechanism. Boost.Cloneable also supports types that are not default-constructable.

There is a fundamental requirement that a common base class type is shared for each type in a given class hierarchy. The user can supply their own base classes, or sensible defaults are generated.

Key features of the library:

Can make any class-type Cloneable with or without modification to its definition
Optional user-supplied base classes
Base types can be queried for the interfaces they support
Clones can be created from base types
Supports multiple inheritance, cloning of sub-objects
Supports types with no default constructors
Customisation of the cloning process
Support for custom allocators
A set of heterogenous containers with emplace semantics for object insertion

Boost.Containers

Author(s): Ion Gaztañaga
Version:
State: stable
Last upload:
Links: Boost Sandbox Download Documentation
Categories: Container
Description: Containers of Movable objects emulation using Boost.Move

Boost.Conversion

Author(s): Vicente J. Botet Escribá
Version: 0.4
State: Stable - Formal review requested - Looking for a review manager
Last upload:2009 October 27
Links: Boost Vault Boost Sandbox Documentation
Categories: Utilities
Description: Generic explicit conversion between unrelated types.

The template function convert_to allows to convert a source type to a target type, using argument dependent lookup to select a specialized convert_to function if available. If no specialized convert_to function is available, boost::conversion::convert_to is used.

The generic convert_to function requires that the elements to be converted are assignable and copy constructible. It is implemented using the Target copy construction from a Source or the Source conversion operator Target - this is sometimes unavailable.

For standard types, we can not add a specialized convert_to function on the namespace std. The alternative to using argument dependent lookup in this situation is to provide a template specialization of boost::conversion::convert_to for every pair of standard types that requires a specialized convert_to.

Boost.Conversion provides:

a generic convert_to function which can be specialized by the user to make explicit conversion between unrelated types.
a generic assign_to function which can be specialized by the user to make explicit assignation between unrelated types.
a generic mca/tie function returning a wrapper which replace assignments by a call to assign_to and conversion operators by a call convert_to.
a generic convert_to_via function which convert a type From to another To using a temporary one Via.
conversion between std::complex of explicitly convertible types.
conversion between std::pair of explicitly convertible types.
conversion between boost::optional of explicitly convertible types.
conversion between boost::rational of explicitly convertible types.
conversion between boost::interval of explicitly convertible types.
conversion between boost::chrono::time_point and boost::ptime.
conversion between boost::chrono::duration and boost::time_duration.
conversion between boost::array of explicitly convertible types.
conversion between Boost.Fusion sequences of explicitly convertible types.

Boost.Convert

Author(s): Vladimir Batov
Version: 0.36
State: Review Requested
Last upload: 2009, Mars 02
Links: Boost Vault
Categories: String And Text Processing
Description: Extensible framework for a uniform approach to type-to-type conversions in general. It builds on the lexical_cast past experience, offers the already familiar conversion functionality and more:

simple and better/safe conversion-failure check;
throwing and non throwing conversion-failure behavior;
support for the default value to be returned when conversion fails;
formatting support based on the standard I/O Streams and the standard (or user-defined) manipulators (like std::hex, std::scientific, etc.);
locale support;
support for boost::range-compliant char and wchar_t-based string containers (std::string, std::wstring, char const*, wchar_t const*, char array[], std::vector<char>, etc.);
no DefaultConstructibility requirement for the Target type;
room to grow.

Boost.Crypto

Author(s): Kasra
Version:
State: (This is not even at beta stage targeted for suggestions and etc ONLY)
Last upload:2009 Jan 20
Links: Boost Vault
Categories: DataCommunication
Description: A library which provides larger number of secure and cryptographic services to the system.

Boost.ConstantTimeSize

Author(s): Vicente J. Botet Escribá
Version: 0.1
State: Stable
Last upload:2008 Oct 14
Links: Boost Vault Boost Sandbox
Categories: Containers
Description: Boost.ConstantTimeSize defines a wrapper to the STL container list giving the user the choice for the complexity of the size function: linear time, constant time or quasi-constant.

In future versions the library could include a similar wrapper to slist.

Boost.Coroutines

Author(s): Giovanni P. Deretta
Version:
State:
Last upload:2008 Mars 05
Links: Boost Sandbox Boost Vault
Categories: Concurrent Programming
Description: The Boost.Coroutine library contains a family of class templates that wrap function objects in coroutines. Coroutines are a generalization of subroutines that can return and be reentered more than once without causing the destruction of automatic objects.

Coroutines are useful whenever it is necessary to keep state across a function call, a job usually reserved to stateful function objects.

Boost.Dataflow

Author(s): Stjepan Rajko
State: Rewriting ongoing
Version:
Last upload:
Links: Documentation Boost Sandbox
Categories: DataCommunication
Description: Dataflow is a generic library for dataflow programming. Dataflow programs can typically be expressed as a graph in which vertices represent components that process data, and edges represent the flow of data between the components. As such, dataflow programs can be easily reconfigured by changing the components and/or the connections.

Boost.Egg

Author(s): Shunsuke Sogame
State:
Version: 0.91.0
Last upload: 30 Mars 2008
Links: Documentation SVN repository Boost Vault
Categories: Function Objects And Higher-order Programming
Description: Egg is a header-only library for building Polymorphic Function Object which can be used with Boost.Lambda. Such a function object is called a Major Function Object. Egg mainly provides three components:
- Function Builders which build Little Functions into Major Function Objects.
- Function Adaptors which take Polymorphic Function Objects then return adapted ones.
- Function Objects which are ports of famous function templates.

Boost.Endian

Author(s): Beman Dawes
Version:
State:
Last upload:2008 Nov 26
Links: Boost Sandbox
Categories: Portability
Description: Provides integer-like byte-holder binary types with explicit control over byte order, value type, size, and alignment. Typedefs provide easy-to-use names for common configurations.

These types provide portable byte-holders for integer data, independent of particular computer architectures. Use cases almost always involve I/O, either via files or network connections. Although portability is the primary motivation, these integer byte-holders may also be used to reduce memory use, file size, or network activity since they provide binary integer sizes not otherwise available.

Boost.Euclid

Author(s): Andreas Harnack
Version: 0.0.3
State:
Last upload:2008 Nov 26
Links: Boost Vault
Categories: Math And Numerics
Description: Euclidean vector class templates providing Orientational analysis on geometrical dimensions.

Boost.Extension

Author(s): Jeremy Pack
Version:
State:
Last upload:2008 Nov 26
Links: Blog Download Headers Boost Sandbox Libs Boost Sandbox
Categories: Reflective Programming
Description: The Boost.Extension library has been developed to ease the development of plugins and similar extensions to software using shared libraries. Classes, functions and data can be made available from shared libraries and loaded by the application.

Boost.Explore

Author(s): Jeff Garland, Jared McIntyre
Version:
State:
Last upload:2008 Mars 22
Links: Boost Sandbox
Categories: Containers Input/Output
Description: Boost.explore is a library that provides for the output of data from containers or ranges.

Boost.Fiber

Author(s): Oliver Kowalke
Version:
State:
Last upload:2008 Oct 30
Links: Boost Vault
Categories: Concurrent Programming
Description: Boost.Fiber implements lightweight threads of execution - so called fibers

Boost.Fsm

Author(s): Andrey Semashev
State:
Version:
Last upload:
Links: Boost Vault
Categories: Data Structures
Description:The Boost.FSM library is an implementation of FSM (stands for Finite State Machine) programming concept.

There are many cases when a developer would like to distinguish behavior of a given object depending on some conditions or its internal state. For example, while developing software to control an charging turnstile a programmer would like to separate states in which the turnstile may persist: an idle state, when the device awaits for another passenger that would like to pass; a processing state, when the passenger have come and put his ticket into the device; and the passing state, when the turnstile lets the passenger pass through. In fact, each state describes a different reaction of the machine at the same events. That's why a passenger may only pass after paying for ticket. Obviously, the turnstile have to be able to change its internal state in order to function properly, this is called state switching or transitions between states (or just transitions for short). This implementation is aimed to ease the creation of such state machines in C++. It supports constructing passive automatons (which means that every action the machine performs is a response to some external event) with finite number of states and finite number of transitions (that is why they are called finite state machines). The main goals of the library are:

Simplicity. It should be very simple to create state machines using this library.
Performance. The state machine infrastructure should not be very time and memory-consuming in order to be applicable in more use cases.
Extensibility. A developer may want to add more states to the existing state machine, for example, the maintenance state for the turnstile mentioned above, and this addition should be relatively safe since it shouldn't interfere with the existing states. The developer should also be able to specify additional transitions and events for the machine with minimum modifications to the existing code.

Boost.GGL

Author(s): Barend Gehrels, Bruno Lalande
Version: Preview 4 (version 0.4)
State: Preview
Last upload: 2009 February 17
Description: Generic Geometry Library
Links: Web site Boost Sanbox Download
Categories: Math And Numerics

Boost.GIL.IO

Author(s): Christian Henning [mailto:chhenning-AT-gmail.com>
Version:
State: Stable
Last upload: 2009 Jan 14
Links: svn repository
Categories: Image Processing
Description:IO extension for boost::gil which allows reading and writing of/in image formats ( tiff, jpeg, ... ).

Boost.Identification

Author(s): Joel Falcou
Version: v0.3
State:
Last upload: 2009 26 June
Links: Boost Vault
Categories: Utilities
Description: Run-time display of type description as a human-readable string

Boost.Interfaces

Author(s): Jonathan Turkanis
Version:
State:
Last upload: 2004
Links: Boost Sandbox
Categories: Patterns
Description: Boost.Interfaces provides a macro-based Interface Definition Language (IDL) which can be used to define C++ class types called interfaces. An interface is a lightweight value type associated with a set of named function signatures. An interface instance can be bound at runtime to any object which implements the interface, i.e., to any object of a type with accessible non-static member functions having the same name and signature as the set of functions associated with the interface. The functions of the bound object can then be invoked through the interface instance using the “dot” operator. Binding is completely non-intrusive: the object's type need not declare any virtual functions or derive from any particluar base class.

Boost.InterThreads

Author(s): Vicente J. Botet Escribá
Version: 0.1.3
State: Stable - Formal review requested - Looking for a review manager
Last upload: 2009 April 02
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming
Description: Boost.InterThreads extends Boost.Threads adding some features:
- thread decorator: thread_decorator allows to define setup/cleanup functions which will be called only once by thread: setup before the thread function and cleanup at thread exit.
- thread_decorator can now decorate a nullary function in addition to a callable function
- thread specific shared pointer: this is an extension of the thread_specific_ptr providing access to this thread specific context from other threads. As it is shared the stored pointer is a shared_ptr instead of a raw one.
- thread keep alive mechanism: this mechanism allows to detect threads that do not prove that they are alive by calling to the keep_alive_point regularly. When a thread is declared dead a user provided function is called, which by default will abort the program.
- thread tuple: defines a thread group where the number of threads is know statically and the threads are created at construction time.
- set_once: a synchronizer that allows to set a variable only once, notifying to the variable value to whatever is waiting for that.
- thread_tuple_once: an extension of the boost::thread_tuple which allows to join the thread finishing the first, using for that the set_once synchronizer.
- thread_group_once: an extension of the boost::thread_group which allows to join the thread finishing the first, using for that the set_once synchronizer.

thread_decorator and thread_specific_shared_ptr are based on the original implementation of threadalert written by Roland Schwarz.

Boost.Introspection

Author(s): Joel Falcou
Version:
State:
Last upload: 2008 October 10
Links: Boost Vault
Categories: Reflective Programming
Description: Class-level introspection traits class prototype

Boost.Introspection2

Author(s): Jean-Louis Leroy
Version:
State:
Last upload: 2008 November 04
Links: Boost Sandbox
Categories: Reflective Programming
Description: Class-level introspection traits class prototype

Boost.ITL

Author(s): Joachim Faulhaber
Version: 3.1.0
State: Stable, submitted for review
Last upload: 2009 September 09
Links: Documentation Boost Sandbox Boost Vault
Categories: Containers
Description: The Interval Template Library (ITL) provides intervals and two kinds of interval containers: interval_sets and interval_maps. Interval_sets and maps can be used just as the sets or maps of elements. Yet they are much more space and time efficient when the elements occur in contiguous chunks. This is obviously the case in many problem domains, particularly in fields that deal with problems related to date and time. In addition to common set and map semantics, interval containers are capable to compute with segmentation. A segmentation, e.g. a grid of months, can be intersected into other interval containers and then be iterated over. Finally interval_maps allow for aggregations on associated values, if added intervals overlap with intervals, that are stored in the interval_map. This feature is called aggregate on overlap.

Boost.LockFree

Author(s): Tim Blechmann
Version: v0.2
State:
Last upload: 2009 November 24
Links: Boost Vault Git Documentation
Categories: Concurrent Programming Containers
Description: Provides implementations of lock-free data structures. Lock-free data structures can be accessed by multiple threads without the necessity of blocking synchronization primitives such as guards. Lock-free data structures can be used in real-time systems, where blocking algorithms may lead to high worst-case execution times, to avoid priority inversion, or to increase the scalability for multi-processor machines.

The following data structures are provided:

boost::lockfree::fifo, a lock-free fifo queue
boost::lockfree::stack, a lock-free stack
boost::lockfree::atomic_int, an atomic integer class

Boost.Log

Author(s): Andrey Semashev `andrey.semashev__AT__gmail.com
Version: RC3
State: review version
Last upload: 2009 Fev 8
Links: Home Page Review Version
Categories: Input/Output
Description: This library aims to make logging significantly easier for the application developer. It provides a wide range of out-of-box tools, along with public interfaces ready to be used to extend the library. The main goals of the library are:
- Simplicity. A small example code snippet should be enough to get the feel of the library and be ready to use its basic features.
- Extensibility. A user should be able to extend functionality of the library with regard to collecting and storing information into logs.
- Performance. The library should make as least performance impact on the user's application as possible.

Boost.LUID

Author(s): Vicente J. Botet Escribá
Version: 0.0.0
State: Prototype
Last upload: 2009 Fev 16
Categories: Data Structures
Links: Boost Sandbox Documentation
Description: Boost.LUID simplifies the generation of locally unique identifiers in a wide context.

Locally Unique Identifier or LUID is a special type of identifier used in software applications in order to provide a reference number which is unique in a given context (hence, "Locally" in opposition to "Globally" or "Universally"). Each generated LUID is guaranteed to be unique in its context.

LUID could have many applications. Some examples follow: creating unique identifiers in a database tables, network messages may be identified with a LUID to ensure that this messages are associated to a given session, transactions may be identified by LUIDs.

Note. Please let me know other applications of luids you can have.

Reduced identifier size

An attractive feature of LUIDs when compared to alternatives is the minimal size used by this identifiers, that depends on the number of instances a given context can have (usually 4 bytes). This allows to use them in protocols fixing the size of the references exchanged to less that 16 bytes(as it is the case of UUID and GUID). Usually LUIDs are represented by unsigned integers and have an upper bound value.

Usable as random access index in constant time

Another aspect, and not less interesting is that the access to the information they identify can be done in constant time.

Recovering unused identifiers

A first implementation could consists in a monotonic counter.

The drawback of having a small size is that the number of unique identifier is more limited. This limit will finish by been reached if the application runs a long time. To palliate to this, we need a mechanism to recover the unused identifiers once the identified information is removed. Depending on the application the recovered identifiers should be discarded, reused immediately or frozen during a given duration or a number of times.

Usually they are reused in a first reusable first reused order (fifo), but depending on the implementation this could not be always the more efficient policy. So the user can either constraint this fifo order or let undefined this aspect.

Managing the lack of identifiers

In any case we need to manage with the overflow case, i.e. when there are no more free identifiers. The user could prefer an exception, return an invalid value, use errno, or call to a user defined function which could try to recover from this situation, by re dimensioning the upper bound for example.

Ensuring coherency on reusable identifiers

All this seams to work up to the user do not release the same identifiers twice. As this is an expensive aspect, but usually the applications has its own way to do it. If this is not the case the application could ask to the luid generator to ensure that.

Synchronization on multi threaded or multi process applications

The generation of new LUIDs and the recovering of unused LUIDs must be synchronized. So LUID are better adapted to systems where these operations are done in a reduced scope. Depending on this scope: single thread, multi-threaded process or a node,i.e. multiple process, the synchronization mechanisms vary. In a single thread scope no synchronization is needed. Synchronization on a multi-threaded process can be ensured using a thread mutex.

In addition the synchronization can be ensured internally by the generator, or externally by the user, i.e. the user has already a synchronization mechanism.

LUIDs are not adapted to distributed system (multiple nodes generating and recovering luids) because it needs a coordination between the different nodes which will take too much time. UUIDs and GUIDs are more adapted to this situation. Anyway if the size constraint can not be avoided, one of the nodes could play the master role and the others behaves as slaves. Master and slaves need to work together. This library do not pretend to take in account this use case but, could be the base of such approach.

Persistency

Another aspect is the lifetime of the information to be identified by the luids. It can be the lifetime of the process, the host machine lifetime or persists to a shut down of the host machine using the file-system.

Optimization

The last aspect will be the optimization. Different application have different needs, some have space constraints, and mot of the others have speed constraints.

Boost.MapReduce

Author(s): Craig Henderson
Version: 0.4
Last upload: February 26, 2009
Links: Boost Vault
Categories: Concurrent Programming Algorithms
Description: MapReduce is a programming model and distributed processing platform implementation for generating and processing large data sets using clusters of computers. Pioneered by Google and first presented in 2004, the MapReduce programming model has gained significant momentum in commercial, research and open-source projects since, and Google have updated and republished their seminal paper in 2008.

The scalability achieved using MapReduce to implement data processing across a large volume of CPUs, whether on a single server or multiple machines is an attractive proposition. The Boost.MapReduce library is a MapReduce implementation across a plurality of CPU cores rather than machines. The library is implemented as a set of C++ class templates, and is a header-only library. It does, however, depend upon many other Boost libraries, such as Boost.System, Boost.FileSystem and Boost.Thread.

Boost.Mirror

Author(s): Matus Chochlik
Version: 0.3.8
Last upload: November 26, 2009
Links: Boost Vault Boost Sandbox C++0x version online docs for the C++0x version
Categories: Reflective Programming
Description: The aim of the Mirror library is to provide useful meta-data at both compile-time and run-time about common C++ constructs like namespaces, types (and as an important special case typedef-ined types), classes and their base classes and member attributes, instances, etc. and to provide uniform and generic interfaces for their introspection.

Boost.Monotonic

Author(s): Christian Schladetsch
Version:
State: On going
Last upload:
Links: Boost Sandbox
Categories: Memory Containers
Description: Monotonic allocators

Boost.Move

Author(s): Ion Gaztañaga
Version:
State: stable
Last upload:
Links: Boost Sandbox [http://www.drivehq.com/web/igaztanaga/libs/move_semantics/ Documentation] Download
Categories: Generic Programming Language Features Emulation
Description: Move semantics emulation library

Boost.MPL.Ext

Author(s): Larry Evans
Version:
State: draft
Last upload:February 12, 2009
Links: while_ in Boost Vault and_seq in Boost Vault
Categories: Template Metaprogramming
Description: Some MPL extensions

Boost.MSF

Author(s): Marco Costalba
Version: 1.2.2
State:
Last upload: 2008, Juin 07
Links: Boost Vault
Categories: Function Objects And Higher-order Programming
Description: The Boost.multi_signature_function library is an extension of Boost.Function that allows to define a boost::function on more then one signature. The Boost.Function library contains a family of class templates that are function object wrappers. Please refer to Boost.Function documentation for reference.

The Boost.multi_signature_function library could be used as a building block in more complex components. In the example directory are presented a dynamic dispatcher and an object factory.

Boost.Msm

Author(s): Christophe Henry
Version: 1.10
State:
Last upload:
Links: Boost Vault Boost Sandbox
Categories: Data Structures
Description: Msm is a framework which enables you to build a Finite State Machine in a straightforward, descriptive and easy-to-use manner . It requires minimal effort to generate a working program from an UML state machine diagram. This work was inspired by the state machine described in the book of David Abrahams and Aleksey Gurtovoy “C++ Template Metaprogramming” and adds most of what UML Designers are expecting from an UML State Machine framework(entry/exit actions, guards, composite states, orthogonal zones, history...).

Boost.NumericBindings

Author(s): Rutger ter Borg
Version: v1
State: stable
Last upload: 2009, November 27
Links: Boost Sandbox v1 Boost Sandbox
Categories: Math And Numerics
Description: Boost.Numeric_Bindings is a C++ library for numeric computing. It is a generic layer between data containers and linear algebra algorithms.

For the data container part, it supports both compile-time statically sized and run-time dynamically sized vectors, matrices, through a traits system. Currently it includes traits for C-arrays, for standard vectors, for uBLAS' containers, Eigen containers, TNT, Boost.Array, to name a few. It offers compile-time inspection, iterators, and views on all mentioned containers.

For the algorithm part, it provides a C++ interface to algorithms offered by BLAS, LAPACK, and more. This covers algorithms from most vendor-provided math libraries, such as the reference BLAS, ATLAS, Intel's MKL, AMD's CML, NVidia's CUDA, etc..

Boost.Overload

Author(s): Marco Cecchetti
Version: 0.3.0
State:
Last upload: 2007, Oct 30
Links: Boost Vault
Categories: Function Objects And Higher-order Programming
Description: Boost Overload behaves as an overloaded Boost Function.

Boost.Polygon

Author(s): Simonson, Lucanus J
Version: v0.1
State: On review schedule
Last upload: 2009 February 17
Links: Boost Sanbox
Categories: Math And Numerics
Description: The boost polygon library provides algorithms focused on manipulating planar polygon geometry data. Specific algorithms provided are the polygon set operations (intersection, union, difference, disjoint-union) and related algorithms such as polygon connectivity graph extraction, offsetting and map-overlay. An example of the disjoint-union (XOR) of figure a and figure b is shown below in figure c. These so-called Boolean algorithms are of significant interest in GIS (Geospatial Information Systems), VLSI CAD as well al other fields of CAD, and many more application areas, and providing them is the primary focus of this library. The polygon library is not intended to cover all of computational geometry in its scope, and provides a set of capabilities for working with coordinates, points, intervals and rectangles that are needed to support implementing and interacting with polygon data structures and algorithms. Specifically, 3d and non-Cartesian/non-planar geometry is outside of the scope of the polygon library.

Boost.Process

Author(s): Julio M. Merino Vidal
Version: v0.1
State:
Last upload:
Links: Boost Sandbox
Categories: System
Description: Provides a flexible framework for the C++ programming language to manage running programs, also known as processes. Among other functionality, this includes the ability to manage the execution context of the currently running process, the ability to spawn new child processes, and a way to communicate with them them using standard C++ streams.

Boost.Plot

Author(s): Jacob Voytko & Paul A. Bristow
Version: v0
State: Under development, especially documentation, but usable.
Last upload: Jan 2009
Links: Boost Plot
Categories: Image Processing
Description: Provides a way of plotting simple 1 and 2D graphs in Scalable Vector Graphic (svg) format directly from C++ code. The graphs are high quality when displayed on a wide variety of display sizes, from mobile phone to big screen, or when printed, but the graph files are tiny and fast enough to be done in near real-time. Fine control of appearance is provided in C++ (but with defaults and optional scaling of axes) so graphs can be produced in a very few lines of code. Current documentation is a mess but Very much improved documentation is nearly complete using Doxygen: meanwhile there are lots of examples.

Boost.Reflection

Author(s): Jeremy Pack
Version:
State:
Last upload:2008 Aug 08
Links: Blog Download Boost Sandbox Headers Boost Sandbox
Categories: Reflective Programming
Description: The goal of this library is to provide runtime reflection for C++ classes, and to allow the same across shared library boundaries. It is an offshoot of the Extension library, which provides dynamic class loading across shared libraries.

Boost.Reflection does not provide automatic reflection of classes. Instead, the class data must be manually reflected. This does offer some benefits however:

This can result in better performance, since only the necessary functions are reflected.
Arbitrary classes can be reflected without modification.
It is possible to make a reflected interface that is quite different from the original interface.

Boost.RendezVous

Author(s): Vicente J. Botet Escribá
Version: 0.3.2
State: Quite Stable
Last upload: 2009 May 11
Links: Boost Vault Boost Sandbox
Categories: Concurrent Programming
Description: Concurrent components may interact in different ways: they may access the same objects by, for example, executing functions of these objects; or they may communicate directly by executing functions of each other. These library will provide the so-called rendezvous mechanism for handling direct communication between active objects.

Boost.RPC

Author(s): Stjepan Rajko
Version:
State:
Last upload: 2007
Links: Boost Sandbox
Categories: Distribued Programming
Description: This is a prototype framework for a remote procedure call implementation using Boost libraries,

specifically Boost.Asio for network communication, Boost.Serialization for marshaling, and futures for handling of returned values.

The framework supplies both server-side and client side components that allow remote procudure calls to be made, and parameters/results to be marshaled between the client and the server. A remote procedure call is executed as follows:

# on the client, the function id and the arguments are serialized and sent over the network # the server receives the serialized call, unserializes the id and arguments and executes the call # if applicable, the results of the call are serialized and sent back over the network to the client

Boost.RTL

Author(s): Arkadiy Vertleyb, Dmitriy Arapov
Version:
State:
Last upload: 2006 December 06
Links: Boost Sandbox
Categories: Database
Description: RTL is an attempt to create a facility that would be free from the above drawbacks, and make relational tables and relational operations convenient to use from a C++ program.

Boost.Singleton

Author(s):
Version:
State:
Last upload:
Links: [ Boost Sandbox]
Categories: Patterns
Description:

Boost.SmartPtr.UniquePtr

Author(s): Howard Hinnant <hinnant@…>
Version:
State:
Last upload: 2009 Jan 3
Links: Documentation & Download
Categories: Generic Programming
Description: unique_ptr is a class template smart pointer currently in the C++0X CD1 draft. It is intended to be a safer and more flexible replacement for auto_ptr. It represents sole (unique) ownership of a resource such as memory (like auto_ptr).

The actual C++0X unique_ptr makes use of a new C++ language feature called rvalue reference which is similar to our current reference (&), but spelled &&. This emulation is intended to capture most of the behavior of the C++0X unique_ptr but work with C++03 compilers. Furthermore this emulation makes use of boost library facilities and has been placed in the boost namespace. Though at the time of this writing, this library is not part of the official boost library release.

Boost.SafeInt

Author(s): Ziv Levi and Omer Katz
Version: v0.0
State: Draft
Last upload: 2009 June 20
Links: Boost Vault
Categories: Math And Numerics
Description: Safe integer types

StableVector

Author(s): Joaquín M López Muñoz
Version:
State: Draft
Last upload:
Links: Stable Vectors
Categories: Containers
Description: a container mimicking the interface of std::vector except that it provides iterator and reference stability at the expense of losing memory contiguity.

Boost.STM

Author(s): Justin E. Gottchlich , Vicente J. Botet Escribá
Version: 0.1
State: work on going
Last upload: 2009 Sep 19
Links: Web Site Downloads Boost Sandbox Documentation
Categories: Concurrent Programming
Description: Transactional memory (TM) is a new parallel programming mechanism that reduces the complexity of parallel programming. TM reduces parallel programming complexity by abstracting away the necessary synchronization mechanisms from the parallel code, allowing the programmer to write parallel applications without worry of deadlocks, livelocks or race conditions.

Transactional memory is an active research interest for many academic and industry institutions with many open questions about its behavior.

TBoost.STM is a C++ lock-based software transactional memory (STM) library. Our approach to STM is to use only native language semantics while implementing the least intrusive, most type-safe object oriented solution possible.

TBoost.STM provides:

Optimistic concurrency
ACI transactions

o Atomic: all operations execute or none do o Consistent: only legal memory states o Isolated: other txes cannot see until committed

Language-like atomic transaction macro blocks
Closed, flattened composable transactions
Direct and deferred updating run-time policies
Validation and invalidation conflict detection policies
Lock-aware transactions
Programmable contention management, enabling programmers to specify forward progress mechanisms
Isolated and irrevocable transactions for transactions that must commit (i.e., I/O transactions)

Boost.Synchro

Author(s): Vicente J. Botet Escribá
Version: 0.3.2
State: work on going
Last upload: 2009 May 11
Links: Boost Vault Boost Sandbox Documentation
Categories: Concurrent Programming
Description:
- A uniform usage of Boost.Thread and Boost.Interprocess synchronization mechanisms based on lockables(mutexes) concepts and locker(guards) concepts.
  - lockables traits and lock generators,
  - generic free functions on lockables as: lock, try_lock, ...
  - locker adapters of the Boost.Thread and Boost.Interprocess lockers models,
  - complete them with the corresponding models for single-threaded programs: null_mutex and null_condition classes,
  - locking families,
  - semaphore and binary_semaphore,
  - condition_lockable lock which put together a lock and its associated conditions.
- A coherent way exception based timed lock approach for functions and constructors,
- A rich palette of lockers as
  - strict_locker, nested_strict_locker,
  - condition_locker,
  - reverse_locker, nested_reverse_locker,
  - locking_ptr, on_dereference_locking_ptr,
  - externally_locked,
- array_unique_locker on multiple lockables.
- Generic free functions on multiple lockables lock, try_lock, lock_until, lock_for, try_lock_until, try_lock_for, unlock * lock adapters of the Boost.Thread and Boost.Interprocess lockable models,
  - lock_until, lock_for, try_lock_until, try_lock_for
- A polymorphic lockable hierarchy.
- High-level abstractions for handling more complicated synchronization problems, including

o monitor for guaranteeing exclusive access to an object.

Language-like Synchronized Block Macros

Boost.Task

Author(s): Oliver Kowalke
Version: 0.2.1
State: Quite Stable
Last upload: 2009 June 25
Links: Boost Vault Boost Sandbox
Categories: Concurrent Programming
Description: execute tasks in threadpool, in new thread or as sub-task and let the result be transfered via a future. support task interruption, work-stealing and fork/join semantics

Boost.TimerQueue

Author(s): John Q. Smith
Version: 0.1
State: On going
Last upload: 2009 June 03
Links: Boost Vault
Categories: Concurrent Programming
Description: Timer Queue is a library that allows you to specify some arbitrary future time at which to be handed back a value that you supply at timer creation.

Boost.ThreaderJoiner

Author(s): Vicente J. Botet Escribá
Version: 0.4.1
State: Quite Stable
Last upload: 2009 Mars 01
Links: Boost Vault Boost Sandbox
Categories: Concurrent Programming
Description: Threader/Joiner as proposed by Kevlin Henney `Preliminary Threading Library Proposal for TR2

Boost.Tree

Author(s): Bernhard Reiter
Version:
State:
Last upload: 2008 Nov 30
Links: Boost Sandbox
Categories: Containers
Description: TR2 Proposal text: Tree Structures and Related Concepts for the C++ Standard Library (TR2)

Boost.Unicode

Author(s): Graham Barnett & Rogier van Dalen
Version:
State:
Last upload: February 12, 2009
Links: Boost Vault
Categories: String And Text Processing
Description: The Boost Unicode library aims to bring Unicode to C++ without requiring intricate knowledge of the Unicode standard, while allowing Unicode experts to do advanced things.

Boost.Unicode2

Author(s): Mathias Gaunard
Version: 0.1
State:
Last upload: August 27, 2009
Links: Boost Vault
Categories: String And Text Processing
Description: This library aims at providing the foundation tools to accurately represent and deal with natural text in C++ in a portable and robust manner, so as to allow internationalized applications, by implementing parts of the Unicode Standard.

This library is environment-independent and deliberately chooses not to relate to the standard C++ locale facilities as well as the standard string facilities, judged ill-suited to Unicode.

The current version is locale-agnostic, but a subsystem for tailored locale behaviour may be added in the future.

Boost.XML

Author(s): Stefan Seefeld
Version:
State:
Last upload: 2008
Links: Boost Sandbox
Categories: String And Text Processing XML
Description: XML parser

Other Open Source libraries

This page contains other libraries that work well with Boost.

ASL

Author(s): Sean Parent and Mat Marcus - Adobe
Version: 1.0.39
State: Released
Last upload: November 6, 2008
Links: Home page
Description: Adobe Source Libraries (ASL) provides peer-reviewed and portable C++ source libraries. The libraries are intended to be widely useful, leveraging and extending both the C++ Standard Library and the Boost Libraries.

async

Author(s): Edd Dawson
Version: 0.2.3
State:
Last upload: 15 January 2008
Links: Web Site Download
Categories: Concurrent Programming
Description: async is a C++ library to allow the calling of functions and functors in an asynchronous manner, thereby making it easier to improve the level of concurrency and parallelism in your applications.

coco

Author(s): Edd Dawson
Version: 0.2.0
State:
Last upload: 23 Feb 2008
Links: Web Site Download
Categories: Concurrent Programming
Description: coco is a library that implements the Boost.Thread interface but is written in terms of the operating system’s native cooperative threading mechanism, whether that be Fibers on Windows, or the <ucontext.h> functions on POSIX machines.

This means that multi-threaded programs written using Boost.Thread can now be run in a single thread. This is useful for debugging and testing purposes, where it is necessary to look at algorithmic correctness in isolation from correctness of synchronisation.

Poet

Author(s): Frank Mori Hess
Version:
State:
Last upload: June 25, 2008
Links: Home Page
Categories: Concurrent Programming
Description: libpoet is a C++ parallel programing library. It provides support for easily creating active objects, creating monitor objects, and automatically validating mutex locking order.

Active objects provide concurrency and thread-safety, since each active object executes in its own thread. Futures are employed to communicate with active objects in a thread-safe manner. To learn more about the active object concept, see the paper "Active Object, An Object Behavioral Pattern for Concurrent Programming." by R. Greg Lavender and Douglas C. Schmidt. Some of the more important active object classes in libpoet are poet::active_function, poet::future, and poet::scheduler.

Monitor objects provide thread-safety via automatically locked access to an object. See the paper "Monitor Object, An Object Behavioral Pattern for Concurrent Programming" by Douglas C. Schmidt for more information about monitor objects. The poet::monitor_ptr, poet::monitor, and poet::monitor_base classes in libpoet provide support for monitor objects.

Finally, the poet::acyclic_mutex class provides a wrapper for mutex classes which adds automatic validation of a program's mutex locking order. Following a consistent locking order ensures your program will not deadlock due to problems such as "deadly embrace" or the "dining philosophers" problem.

TBB

Author(s): Intel
Version: 2.1
State: stable release
Last upload: June 7, 2008
Links: Home page
Categories: Concurrent Programming
Description: Intel® Threading Building Blocks (TBB) offers a rich and complete approach to expressing parallelism in a C++ program. It is a library that helps you take advantage of multi-core processor performance without having to be a threading expert. Threading Building Blocks is not just a threads-replacement library. It represents a higher-level, task-based parallelism that abstracts platform details and threading mechanism for performance and scalability and performance.

tscb

Author(s): Helge Bahmann
Version: 0.1
State:
Last upload: 2008 Nov 23
Links: Documentation+Download
Categories: Concurrent Programming
Description: Thread-safe callback services.

This library provides classes for notifications via callbacks in multi-threaded programs. In particular, it provides the following services:

Signals and slots: signal_proxy provides an interface through which interested receivers can connect/disconnect callback functions at runtime. signal provides an implementation of this interface and provides senders a mechanism to notify interested receivers, passing specified arguments to each callback function.
I/O readiness: ioready_service provides an interface through which interested receivers can register/deregister for notification on I/O readiness events (i.e. file descriptor ready for reading/writing; cf. poll/select). ioready_dispatcher provides an implementation of this interface that allows waiting (with timeout) for and fetching the required information from the operating system and notifying registered receivers.
Timers: timer_service provides an interface through which interested receivers can register/deregister for notification at specific points in time. timer-queue_dispatcher provides an implementation of this interface, keeping track of all pending timers, deadline when next timer is due, and "premature interruption" if the deadline must be invalidated (e.g. due to a newly-added timer).
Compound event dispatching (or "reactor-style" operation): posix_reactor_service combines the ioready_service, timer_service and workqueue_service interfaces. posix_reactor provides an implementation of this interface and performs all required operations of delivering all requested notifications.

The implementations in this library provide strong thread-safety guarantees, are reentrant, deadlock-free and provide strong consistency guarantees. See section Concurrency and reentrancy below for an exact definition of the guarantees.

Libraries Under Discussion

This page is an index page for discussion of possible libraries as people get their ideas together.

Libraries Wish list

This page contains libraries that people have requested of Boost (mostly on the developer's mailing list). If you're looking for a project, this is a good place to start.

Accumulators.Ext

Suggested by: Vicente J. Botet Escribá
Categories: Math And Numerics
Description: Adding sliding, dependable and cyclic accumulators to Boost.Accumulators.

The accumulator library allows to determine dependency between accumulator, but not between accumulator_sets. I would like to define an accumulator_set c so when we cumulate in two others c1 and c2 accumulator_set we cumulate also in c, some thing like:

typedef dependable_accumulator_set <double, ...> dependable_acc_type;

dependable_acc_type c1, c2;
dependable_acc_type c=c1+c2

dependable_acc_type c3;

c+=c3;

c1(1);
c2(1);
c3(2);
assert(count(c)==3);
assert(sum(c)==4);

How dependable_accumulator_set can be defined? Here follows the interfaces of such a class and the pseudo code, I've named the class dependable_accumulator_set, sorry but I have not found a shorter and better name (may be observed/listened?)

template <typename T, typename F, typename W>
class dependable_accumulator_set : public acumulator_set<T,F,W>
{
public:
    dependable_accumulator_set();
    void add_dependent(dependable_acumulator_set&);
    void remove_dependent(dependable_acumulator_set&);

    template<typename A1>
    void operator ()(A1 const &a1) {
        for (acc in dependents) {
            acc(a1);
        }
        this->accumulator_set_type::operator()(a1);
    }
    dependable_accumulator_set<T,F,W>& operator+=(dependable_accumulator_set<T,F,W>);
    dependable_accumulator_set<T,F,W>& operator-=(dependable_accumulator_set<T,F,W>);
};

template <typename T, typename F, typename W>
dependable_accumulator_set<T,F,W> 
operator+()(dependable_accumulator_set<T,F,W>,dependable_accumulator_set<T,F,W>);

Another variant could be also to have a temporary accumulator that cyclically push its current value on another accumulator.

It will also interesting to have a dependable and cyclic accumulator set. It would be great to integrate these features on a unique class (accumulator_set?) in a clean way.

template <typename T, typename F, typename W, 
          typename DependablePolicy, 
          typename CyclicPolicy>
class accumulator_set;

Cloner

Suggested by: Vicente J. Botet Escribá
Categories: Data Structures
Description: Clone framework

ConstraintsProgramming

Suggested by: Vicente J. Botet Escribá
Categories: []
Description: Constraints programming is a programming paradigm where relations between variables are stated in the form of constraints. Constraints differ from the common primitives of imperative programming languages in that they do not specify a step or sequence of steps to execute, but rather the properties of a solution to be found. This makes Constraint Programming a form of declarative programming.

typedef bounded<int, closed<1>, closed<2> > domain;
problem_solver<domain, domain> p;
p.add_constraint(_1 + _2 == 3);
for {problem::iterator it = p.solutions(); it != p.end(); ++it) {
    domain a, b;
    tie(a,b) = *it;
    std::cout << "[" << a << ", " << b << "]" << std::endl;
}

Database

Suggested by: elfring
Categories: Database
Description: a library for database interaction.

DenseSet

Suggested by: Vicente J. Botet Escribá
Categories: Containers
Description: Implementation of dense set of integers using intervals.

Enums

Suggested by: Vicente J. Botet Escribá
Categories: Data Structures
Description: Enums traits.

EnumSet

Suggested by: Vicente J. Botet Escribá
Categories: Containers
Description: STL Set interface for enums.

EnumArray

Suggested by: Vicente J. Botet Escribá
Categories: Containers
Description: Array indexed by Enums.

Frames

Suggested by: Vicente J. Botet Escribá
Categories: Input/Output
Description: Library based on an extension of the Archive concept making it bidirectional.

From wikipedia "A frame is a data packet of fixed or variable length which has been encoded by a data link layer communications protocol for digital transmission over a node-to-node link. Each frame consists of a header frame synchronization and perhaps bit synchronization, payload (useful information, or a packet at higher protocol layer) and trailer. Examples are Ethernet frames and Point-to-point protocol (PPP) frames."

The Boost.serialization saving archive concept allows to save serializable data at the end of the archive, and the loading archive concept allows to read serializable data from the beginning of the archive. The saving frame concept will allows to save serializable data either at the end or the begin of the frame, and the loading frame concept allows to read serializable data from the beginning or the end of the archive. I'm not sure which syntax will be the more appropriated. The serialization library use the <<, >>, and & operators that are associative from left to right. We need the equivalent operators from right to left. <<=, >>=, and &= seams to be the more natural candidates but I don't know if it is correct in C++ to define this operators with this prototype

template <typename T> frame& operator<<=(const T&, frame&);
template <typename T> frame& operator>>=(const T&, frame&);
template <typename T> frame& operator&=(const T&, frame&);

h1 >>= h2 >>= sf << t2 << t1

is equivalent to

(h1 >>= (h2 >>= ((sf << t2) << t1)))

and should be equivalent to

sa & h1 & h2 & t2 & t1

if sf and sa were empty.

The main difference is that we can do it hierarchically. The top layer will create a frame, and serialize its own information elements.

frame sf;
h_n >>= sf  << p_n << t_n;

Then this top layer will use a primitive of the lower level having as parameter the frame as payload.

primitive_n-1(sf);

A primitive at the k level will add its own header and trailer information element to the payload of the upper level

void primitive_k(frame& sf) {
    // ...
    h_k >>= sf  << t_k;
    // ...
    another_primitive_k_1(sf);
    // ...
}

So the frame allows to serialize top-down. To get the same result with the archive concept the serialization must be done bottom-up, needing to chain each one of the information element in a list and only when we have all off them we can start the serialization. I think that the frame approach should be more efficient because it avoid to store in dynamic memory the information elements to be serialized, instead they are serialized directly.

Loading a frame works as loading an archive, except that we can load also at the end of the frame. This avoids to load the complete archive to load the trailer of the lower levels.

lf >>= h_1;
// ...
t_1 << lf;

In addition, it would be great to have saving/loading frames (I'm not sure but I think that an archive can not be saving and loading at the same time). The same frame can be used as loading, analyzing only some lower levels, and as saving in order to construct other lower levels. This will be very useful for gateways and routers.

| L4 |<------------------------------>| L4 |
| L3 |    |     ADAPTATION     |      | L3 |
| L2 |<-->| L2 |          | X2 | <--> | X2 |
| L1 |<-->| L1 |          | X1 | <--> | X1 |

It would be great also that the same data that can be serialized on archives, could be serializable on a frame using the same save function. But this works only when we save at the end of the frame. Let me see this using a little example: Class C has 3 information elements to serialize (a, b and c). So the save functions could be something like

template <typename ARCHIVE>
void C::save(ARCHIVE& sa) {
    sa & a & b & c;
}

This save function works well from left to right, but can not be used when saving at the beginning of a frame, because the expected result when saving at the beginning is

a b c sa

but the result will be

c b a sa

So unfortunately we need a different save function

template <typename FRAME>
void C::save(FRAME& sa, begin_tag&) {
    a >>=  b >>= c >>= sa;
    // a >>=  (b >>= (c >>= sa));
}

ObjectRole

Suggested by: Vicente J. Botet Escribá
Categories: Containers Data Structures
Description: Change the behaviour of an object depending on the roles it plays.

Quartets

Suggested by: Vicente J. Botet Escribá
Categories: Containers Data Structures
Description: Quartet are half an octet, i.e. 4 bits taking values from 0..15, and usually represented by chars '0'-'9' 'A'-'F'. There are some container specializations as std::string, std::vector and boost::array that could be of interest to some applications. They are also used when a decimal number is encoded using the BCD format (binary coded decimal) or to encode telephone numbers.

SpreadSheet

Suggested by: Vicente J. Botet Escribá
Categories: []
Description: Allows to manage with the underlying concepts of a Spreadsheet but without displaying them.

Defines cells that can be organized in a classical grid consisting of rows and columns, or any other structure as for example a tree. Each cell could contains alphanumeric text or numeric values but can also contain any other value. A spreadsheet cell may alternatively contain a formula that defines how the contents of that cell is to be calculated from the contents of any other cell (or combination of cells) each time any cell is updated.

It seems natural to use Boost.Proto to define the DSL for the cell formulas.

space sh;
space::cell<int> c1(sh), c2(sh), c3(sh);
c1.expr=1;
c2.expr=2;
c3.expr=c1+c2;
sh.refresh();
std::cout<< c1.value() << ", " << c2.value() << ", " << c3.value() << std::endl;

sheet sh(2,3);
sheet::cell<int> c01(sh,0,1), c02(sh,0,2), c03(sh,0,3);
c01.expr=1;
c02.expr=2;
c03.expr=rel_cell(c03,0,1)+rel_cell(c03,0,2);
sh.refresh();
std::cout<< c01.value() << ", " << c02.value() << ", " << c03.value() << std::endl;
c11.expr=5;
c12.expr=8;
c13.expr=c03.copy(); 
sh.refresh();
std::cout<< c11 << ", " << c12 << ", " << c13 << std::endl;

Abandoned

Boost.ConceptTraits

Author(s): Terje Slettebø and Tobias Schwinger
Version:
State:
Last upload: 2004 September 12
Categories: Correctness And Testing Language Features Emulation
Links: Documentation Original Download

Last Download

Description:Overload on Concepts of template parameter types, using enable_if and some class traits.

Libraries Listed by Category

See Boost library documentation by Category for a list of the already approved Boost libraries by category.