Release Notes

Version 5.3 (2001-11-24)

This release contains enhancements to the kernel, various libraries and the embedding features. It also contains preliminary versions of features which are still under development. Incompatibilities with the previous version should be very minor.

Libraries

lib(ic) nearing completion: This is the new hybrid real/integer interval constraint solver. Functionality added since the last, preliminary release: nonlinear constraints, strict inequalities, reified constraints.
New Library: lib(notify_ports): Implements a form of one-to-many message passing, where send and receive ports are ECLiPSe data structures. A typical application is the implementation of AC-4 style algorithms.
New Library: lib(viewable): Experimental release of the ECLiPSe side of the visualisation architecture planned for future releases. The viewable library allows you to declare in your ECLiPSe program arrays of data elements which will be viewable by future visualisation clients.
lib(branch_and_bound) enhancements: Incorporates a new single-pass, non-restart algorithm (strategy continue), which has been made the default. It is often, but not necessarily, faster than the old default (strategy step) and supersedes the minimize/n predicates of the fd library.
lib(graph_algorithms) enhancements: New predicates: minimum_spanning_tree/4, minimum_spanning_forest/5, single_pair_shortest_path/5, single_pair_all_shortest_paths/5.
lib(eplex) enhancements

Enbedding and Interfaces

Unified High-Level External Language Interface Support
Tcl/Tk-ECLiPSe Interface: Increased compatibility between embedded and remote Tcl interfaces; (support for ECLiPSe handler in to-ECLiPSe queues). Support for creation of; peer queues from the ECLiPSe side.
Java-ECLiPSe Interface: major new features (see Embedding and Interfacing manual chapter for more details):
Visual Basic Interface Sample Code: This is no longer supported by the ECLiPSe group and has therefore been removed from the distribution. We have made the code freely available for anyone interested to take over.
Environment variables: Java and Tcl/Tk embedding now work without the need for setting LD_LIBRARY_PATH on Unix or PATH on Windows.
Runtime subset: For the deployment of ECLiPSe-based applications, this release contains a separately packaged (eclipse_rt.tgz) runtime subset of the system.

Development Environment

lib(document): structure declarations can now be documented using comment/2 directives in a format similar to predicate comments.
emacs mode for ECLiPSe is significantly enhanced.

Kernel features

Revised triggering mechanism for the garbage collector, reducing garbage collection overhead. The new global flag gc_policy can be used to choose between a slower memory-greedy policy (fixed) and faster but more memory-intensive one (adaptive, the default).
New control features for raising events on failures.
New global flag version_as_list returns version information as list of major version number, minor version number and build number. Lexicographic comparison can be used on such lists to compare the version age.
New syntax option read_floats_as_breals forces floating point numbers in the input to be parsed as bounded reals (intervals) rather than floats.
New stream property handle_io added, indicating that the stream can currently handle I/O.
The global flag hostname now does a better job of returning a full pathname for the host.

Incompatibilities

Some minor changes and incompatibilities: see Java-ECLiPSe interface changes from 5.2 to 5.3
The default timer for after-events is now real rather than virtual. This was changed because virtual timers are not available on all platforms and in all variants of ECLiPSe systems. When virtual timers are available, the setting can be changed by calling set_flag(after_event_timer, virtual).
The default strategy in lib(branch_and_bound) has changed. If the new behaviour should be worse, you can get the old behaviour by explicitly choosing strategy:step.
If a system error is raised when connect/2 tries to make a client socket connection (e.g. because the connection is refused), the socket stream is closed. Previously the stream remained open and the user can attemp another connection. This was changed because under some version of SunOS 5, the socket was left in an undefined state.
The behaviour of select/3 on the null stream has changed: It is now never considered ready for I/O.
The new garbage collection policy may not suit machines with little main memory. In that case, either start ECLiPSe with a smaller global/trail stack limit (-g option or preference setting in tkeclipse), or set the gc_policy flag to fixed.