HOL is a programming environment that enables the proof of theorems and implementation of proof tools.
What sets HOL 4 apart is its ability to combine deduction, execution, and property checking. As a result, it's an ideal platform for those who need to implement complex combinations of these functionalities. And with the latest release, there are even more exciting features to look forward to.
Some of the new additions in this version include a new set comprehension notation, support for SML string notation, and added support for the XEmacs editor. Additionally, case expressions can now include literals as patterns, and inductive definitions are now made with respect to a varying monoset.
Another improvement is that types that use abbreviated patterns are now printed in abbreviated form, and rational numbers and fixed-length integers are now supported. Finally, if you've experienced issues with certain components not compiling under GCC 4, those bugs have been fixed, as has an issue with normalization in natural numbers and integers, and handling of empty strings.
Overall, HOL 4 is an excellent choice for those looking to implement complex combinations of deduction, execution, and property checking. And with the new features and bug fixes in this release, it's more powerful than ever before.
Version 4: N/A