This is a list of some applications and contributions to YAP:
Aleph is an Inductive Logic Programming (ILP) system that supersedes P-Progol.
The FSA Utilities toolbox is a collection of utilities to manipulate regular expressions, finite-state automata and finite-state transducers. Manipulations include automata construction from regular expresssions, determinization (both for finite-state acceptors and finite-state transducers), minimization, composition, complementation, intersection, Kleene closure, etc. In addition to atomic symbols, automata can be defined by means of `predicates' on arcs. Various visualization tools are available to browse finite-state automata. Interpreters are provided to apply finite automata. Finite automata can also be compiled into stand-alone C programs.
Recent versions of FSA are available for SWI-Prolog, SICStus Prolog and YAP. The toolbox comes with an optional graphical user interface (only available under SICStus) and an optional command interpreter. The toolbox can also be applied as a UNIX filter, or as a Prolog library. The toolbox is freely available under GPL.
SceX (pronounce it skech for score (T)eX) is a system that processes textual descriptions of music pieces.