## 1.6 Acknowledgements

Some small parts of the Prolog code of SWI-Prolog are modified versions of the corresponding Edinburgh C-Prolog code: grammar rule compilation and writef/2. Also some of the C-code originates from C-Prolog: finding the path of the currently running executable and some of the code underlying absolute_file_name/2. Ideas on programming style and techniques originate from C-Prolog and Richard O'Keefe's thief editor. An important source of inspiration are the programming techniques introduced by Anjo Anjewierden in PCE version 1 and 2.

Our special thanks go to those who had the fate of using the early versions of this system, suggested extensions or reported bugs. Among them are Anjo Anjewierden, Huub Knops, Bob Wielinga, Wouter Jansweijer, Luc Peerdeman, Eric Nombden, Frank van Harmelen, Bert Rengel.

Martin Jansche (jansche@novell1.gs.uni-heidelberg.de) has been so kind to reorganise the sources for version 2.1.3 of this manual. Horst von Brand has been so kind to fix many typos in the 2.7.14 manual. Thanks! Randy Sharp fixed many issues in the 6.0.x version of the manual.

Bart Demoen and Tom Schrijvers have helped me adding coroutining, constraints, global variables and support for cyclic terms to the kernel. Tom Schrijvers has provided a first clp(fd) constraint solver, the CHR compiler and some of the coroutining predicates. Markus Triska contributed the current clp(fd) implementation as well as the clp(b) implementation.

Tom Schrijvers and Bart Demoen initiated the implementation of delimited continuations (section 4.9), which was used by Benoit Desouter and Tom Schrijvers to implement tabling (section 7) as a library. Fabrizio Riguzzi added a first implementation for mode directed tabling (section 7.3).

The SWI-Prolog 7 extensions (section 5) are the result of a long heated discussion on the mailinglist. Nicos Angelopoulos’wish for a smooth integration with the R language triggered the overall intend of these extensions to enable a smoother integration of Prolog with other languages. Michael Hendrix suggested and helped shaping SWI-Prolog quasi quotations.

Paul Singleton has integrated Fred Dushin's Java-calls-Prolog side with his Prolog-calls-Java side into the current bidirectional JPL interface package.

Richard O'Keefe is gratefully acknowledged for his efforts to educate beginners as well as valuable comments on proposed new developments.

Scientific Software and Systems Limited, www.sss.co.nz has sponsored the development of the SSL library, unbounded integer and rational number arithmetic and many enhancements to the memory management of the system.

Leslie de Koninck has made clp(QR) available to SWI-Prolog.

Jeff Rosenwald contributed the TIPC networking library and Google's protocol buffer handling.

Paulo Moura's great experience in maintaining Logtalk for many Prolog systems including SWI-Prolog has helped in many places fixing compatibility issues. He also worked on the MacOS port and fixed many typos in the 5.6.9 release of the documentation.

Kyndi (https://kyndi.com/) sponsored the development of the engines interface (chapter 11). The final API was established after discussion with the founding father of engines, Paul Tarau and Paulo Moura. Kyndi also sponsored JIT indexing on multiple arguments as well as deep indexing. Kyndi currently supports the implementation of XSB compatible tabling, including well founded semantics and incremental tabling. Theresa Swift, David S. Warren and Fabrizio Riguzzi provided input to realise advanced tabling.