Dear List Members, Through Mark Adams' paper "HOL Zero's Solutions for Pollack-Inconsistency" (2016) linked at the HOL Zero homepage, I became aware of the notion of Pollack-consistency coined by Freek Wiedijk for the property of "a system being able to correctly parse formulas that it printed itself":
Freek Wiedijk: Pollack-inconsistency http://doi.org/10.1016/j.entcs.2012.06.008 http://www.cs.kun.nl/~freek/pubs/rap.pdf It is amusing to see how the parsing and printing functions of John's HOL Light are put on the rack and stretched quite a bit. Also Isabelle and other systems are examined. The interesting point for me was to see that somebody had the same idea. In the R0 implementation, not only a formula, but whole printed proofs can be parsed again. In fact, if it is compiled and started with "make check", R0 loops through all proofs, and this is done twice, with the output of the first run as the input of the second, stopping immediately with an error message if a proof fails or if the output of the two runs differ. This was implemented quite early, so the system was designed from the very beginning to comply with a notion of Pollack-consistency not only in terms of formulae, but in terms of whole proofs. Like for HOL Zero, this was done in order "to achieve the highest levels of reliability and trustworthiness through careful design and implementation of its core components" - quoted from: Mark Adams: HOL Zero's Solutions for Pollack-Inconsistency http://doi.org/10.1007/978-3-319-43144-4_2 http://www.proof-technologies.com/holzero/hzsyntax_itp2016.pdf Concerning HOL4 and HOL Zero, I am looking for introductions to them in the literature. The appropriate candidates seem to be, at the first glance (without having read them already): Mark Adams: Introducing HOL Zero (Extended Abstract) http://doi.org/10.1007/978-3-642-15582-6_25 Konrad Slind, Michael Norrish: A Brief Overview of HOL4 http://doi.org/10.1007/978-3-540-71067-7_6 The latter I found as reference no. 14 of Mark's 2016 paper. Please let me know if you have other suggestions. Kind regards, Ken Kubota ____________________ Ken Kubota http://doi.org/10.4444/100 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ hol-info mailing list hol-info@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/hol-info