Section: New Software and Platforms

DyALog

Participant : Éric Villemonte de La Clergerie [maintainer] .

DyALog on Inria GForge: http://dyalog.gforge.inria.fr/

DyALog provides an environment to compile and execute grammars and logic programs. It is essentially based on the notion of tabulation, i.e. of sharing computations by tabulating traces of them. DyALog is mainly used to build parsers for Natural Language Processing (NLP). It may nevertheless be used as a replacement for traditional PROLOG systems in the context of highly ambiguous applications where sub-computations can be shared.

The current release of DyALog (version 1.14.0) is freely available by FTP under an open source license and runs on Linux platforms for x86 and architectures and on Mac OS intel (both 32 and 64bits architectures). In particular, it has been ported for the CLANG/LLVM compiler used in recent Mac OS systems (Mavericks).

The current release handles logic programs, DCGs (Definite Clause Grammars), FTAGs (Feature Tree Adjoining Grammars), FTIGs (Feature Tree Insertion Grammars) and XRCGs (Range Concatenation Grammars with logic arguments). Several extensions have been added to most of these formalisms such as intersection, Kleene star, and interleave operators. Typed Feature Structures (TFS) as well as finite domains may be used for writing more compact and declarative grammars [135] . Version 1.14.0 now includes an efficient handler for feature-based statistical models, derived from the work on DyALog-SR and now used in FRMG parser.

C libraries can be used from within DyALog to import APIs (mysql, libxml, SQLite, ...).

DyALog is largely used within ALPAGE to build parsers but also derivative softwares, such as a compiler of Meta-Grammars (cf. 5.3). It has also been used for building FRMG, a parser from a large coverage French TIG/TAG grammar derived from a Meta-Grammar. This parser has been used for the Parsing Evaluation campaign EASy, the two Passage campaigns (Dec. 2007 and Nov. 2009) [130] , [134] , and very large amount of data (700 millions of words) in the SCRIBO project. New results concerning FRMG are described in 6.5 .

DyALog is also used to run DyALog-SR , a transition-based dependency parser (see new results in 6.5 )

DyALog and other companion modules (including DyALog-SR ) are available on Inria GForge.