HOL4 vs K Framework
HOL4
hol-theorem-prover.orgK Framework
kframework.orgSide by side
| Figure | HOL4 | K Framework |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | — |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | — | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 0 |
| Spec score · Formal Verification Tools | 8.1 (#9) | 7.5 (#22) |
| Purpose | HOL4 is a proof assistant for higher-order logic and a programming environment for proving theorems and implementing proof tools. | K is a rewrite-based executable semantic framework for defining programming languages, type systems, and formal analysis tools. |
| Support | The community offers help through a mailing list and Zulip chat, while bug reports and feature suggestions go to GitHub issues. | The official site lists Discord as its most direct support channel and also links to a Matrix room. |
| Use cases | The maker describes HOL as particularly suitable for combining deduction, execution and property checking. | The official site links to projects using K, including examples and tools based on K definitions. |
Plans
In their own words
HOL4
HOL4 is a free, interactive proof assistant for higher-order logic, with a programming environment for proving theorems and building proof tools. It supports work that combines deduction, execution, and property checking. Built-in decision procedures and theorem provers can establish many simple theorems, and an oracle mechanism can connect to external programs such as SMT and BDD engines. HOL4 supports higher-order logic and Standard ML, and can produce proof artifacts and counterexamples. It is self-hosted and listed for Linux, macOS, and Windows. A Standard ML compiler is required, with Poly/ML recommended; Moscow ML and MLTon are also supported for building tool executables. Windows installation can use Cygwin or the Windows Linux subsystem with Poly/ML. Moscow ML is another option, but the Windows guide notes that it is slower, lacks some Poly/ML libraries, and cannot run concurrent Holmake builds. HOL includes Emacs modes for syntax display and session interaction, and the installation guide links to Vim plugin documentation. Online materials include a tutorial, quick reference, FAQ, manuals, and generated indexes.
K Framework
K Framework has no write-up on Specifiction yet; its figures are above.