HOL Light vs HOL4
HOL Light
hol-light.github.ioHOL4
hol-theorem-prover.orgSide by side
| Figure | HOL Light | HOL4 |
|---|---|---|
| Price from | — | Free |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 0 | 1 |
| Spec score · Formal Verification Tools | 7.5 (#21) | 8.1 (#9) |
| Documentation | The official site provides a tutorial and a reference manual in HTML and PDF formats. | HOL provides online searchable manuals, reference documentation and a theory dependency graph, and builds a local reference copy during installation. |
| Purpose | HOL Light is a computer program for formally proving mathematical theorems in higher-order logic. | HOL4 is a proof assistant for higher-order logic and a programming environment for proving theorems and implementing proof tools. |
Plans
In their own words
HOL Light
HOL Light has no write-up on Specifiction yet; its figures are above.
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.