Callback Framework for C++

libsigc++ implements a typesafe callback system for standard C++. It allows you to define signals and to connect those signals to any callback function, either global or a member function, regardless of whether it is static or virtual.

It also contains adaptor classes for connection of dissimilar callbacks and has an ease of use unmatched by other C++ callback libraries. Libsigc++ is licensed under the GNU Library General Public License, LGPL.

Features

• Compile time typesafe callbacks (faster than run time checks)
• Typesafety violations report line number correctly with template names (no tracing template failures into headers)
• No compiler extensions or meta compilers required
• Proper handling of dynamic objects and signals (deleted objects will not cause seg faults)
• Extendable API at any level: signal, slot, connection and trackable
• Extensions do not require alteration of basic components
• User definable accumulators
• A variety of adaptors to change the callback signature: bind, hide, retype, compose and lambda call groups
• Various compilers and platforms are supported: gcc, cygwin, mingw32, MS .NET 2003, Sun Forte C++, Compaq C++, Intel C++, IBM AIX, Tru64, IRIX MipsPro.

News

• Provides unnumbered signal and slot templates.
• Supports arbitrary functor types.
• Supports implicit argument type conversions on signal emission.
• Adds support for overloaded functions.
• Borrows powerful accumulator interface from boost::signal.
• Simplifies use of adaptors like sigc::hide(): argument types need not be specified any more (except for sigc::retype_return()).
• More powerful adaptors: position of arguments to hide or bind can be chosen freely; up to 7 arguments can be bound at a time.
• Adds two useful adaptors: sigc::compose(), sigc::exception_catch().
• Adds all-in-one operator sigc::group() with support for lambdas featuring a complete set of lambda selectors and lambda operators.
• Performs only one indirect function call during slot invokation regardless of the number of adaptors used; the direct function calls involved are inline and can be optimized away by the compiler.
• Conforms to the STL naming scheme: only uses small letters.

The libsigc++-1.2 series still is an alternative because it has less prerequisites for the comiler. Andreas Rottmann released some code for CORBA support with libsigc++-1.2. Please send him an email if you think that this is interesting for you! CORBA for libsigc++. Also good to check out are the Erik Thiele and Andreas Rottmann siztes which include some interesting libsigc++ tools like cross-thread support.

Developers