The hol package
The hol package is a Haskell library that implements a higher order logic kernel. It can read proof files in OpenTheory format, and includes a pretty-printer compatible with the standard theory library.
This software is released under the MIT License.
Install
Installing the hol package requires cabal:
git clone https://github.com/gilith/hol.git
cd hol
cabal install --enable-tests
Test
Use cabal to run the test suite:
cabal test
Run
The hol package contains an executable called hol-pkg, which is run as follows:
Usage: hol-pkg INPUT
where INPUT is one of the following forms:
FILE.art : a proof article file
FILE.thy : a theory package file
NAME-VERSION : a specific version of an installed theory package
NAME ... : the latest installed version of a list of packages
The hol-pkg program reads the INPUT to generate a set of theorems, which are pretty-printed to standard output together with the symbols they contain. For example,
hol-pkg unit
reads the latest installed version of the unit theory package to generate a set of 5 theorems, resulting in the following output:
3 type operators: (->) bool unit
6 constants: (=) (!) (==>) (?) (?!) ()
5 theorems:
|- !v. v = ()
|- !f g. f = g
|- !e. ?fn. fn () = e
|- !e. ?!fn. fn () = e
|- !p. p () ==> !x. p x
Profile
Before starting, make sure the GHC system and the GHC text, transformers and parsec libraries are installed with profiling support. On a Debian system the following command installs them:
apt-get install ghc-prof libghc-text-prof libghc-transformers-prof libghc-parsec3-prof
Next use cabal to install the other dependent libraries with profiling support:
cabal sandbox init
cabal configure --enable-library-profiling --enable-profiling --enable-benchmarks
cabal install --only-dependencies --enable-library-profiling
Build the hol package library and benchmark program:
cabal configure --enable-library-profiling --enable-profiling --enable-benchmarks
cabal build
Use the opentheory tool to create a benchmark file:
opentheory info --article -o base.art base
Then use cabal to run the benchmark:
cabal bench
The time and memory allocation profile of the program can be viewed in text format:
less hol-profile.prof
Alternatively the memory allocation profile can be viewed as a graph:
hp2ps -e8in -c hol-profile.hp
ps2pdf hol-profile.ps
xpdf hol-profile.pdf