PublicShow -- A package manager for Prolog

The library(prolog_pack) provides the SWI-Prolog package manager. This library lets you inspect installed packages, install packages, remove packages, etc. It is complemented by the built-in attach_packs/0 that makes installed packages available as libaries.

See also
- Installed packages can be inspected using ?- doc_browser.
To be done
- Version logic
- Find and resolve conflicts
- Upgrade git packages
- Validate git packages
- Test packages: run tests from directory `test'.
Source pack_list_installed is det
List currently installed packages. Unlike pack_list/1, only locally installed packages are displayed and no connection is made to the internet.
See also
- Use pack_list/1 to find packages.
Source pack_info(+Pack)
Print more detailed information about Pack.
Source pack_search(+Query) is det
Source pack_list(+Query) is det
Query package server and installed packages and display results. Query is matches case-insensitively against the name and title of known and installed packages. For each matching package, a single line is displayed that provides:
  • Installation status
    • p: package, not installed
    • i: installed package; up-to-date with public version
    • U: installed package; can be upgraded
    • A: installed package; newer than publically available
    • l: installed package; not on server
  • Name@Version
  • Name@Version(ServerVersion)
  • Title

Hint: ?- pack_list(''). lists all packages.

The predicates pack_list/1 and pack_search/1 are synonyms. Both contact the package server at to find available packages.

See also
- pack_list_installed/0 to list installed packages without contacting the server.
Source pack_install(+Spec:atom) is det
Install a package. Spec is one of
  • Archive file name
  • HTTP URL of an archive file name. This URL may contain a star (*) for the version. In this case pack_install asks for the directory content and selects the latest version.
  • GIT URL (not well supported yet)
  • A local directory name given as file:// URL.
  • A package name. This queries the package repository at

After resolving the type of package, pack_install/2 is used to do the actual installation.

Source pack_install(+Name, +Options) is det
Install package Name. Processes the options below. Default options as would be used by pack_install/1 are used to complete the provided Options.
Source for downloading the package
Directory into which to install the package
Use default answer without asking the user if there is a default action.
If true (default false), suppress informational progress messages.
If true (default false), upgrade package if it is already installed.
If true (default false unless URL ends with =.git=), assume the URL is a GIT repository.

Non-interactive installation can be established using the option interactive(false). It is adviced to install from a particular trusted URL instead of the plain pack name for unattented operation.

Source pack_url_file(+URL, -File) is det
True if File is a unique id for the referenced pack and version. Normally, that is simply the base name, but GitHub archives destroy this picture. Needed by the pack manager.
Source pack_rebuild(+Pack) is det
Rebuilt possible foreign components of Pack.
Source pack_rebuild is det
Rebuild foreign components of all packages.
Source environment(-Name, -Value) is nondet[multifile]
Hook to define the environment for building packs. This Multifile hook extends the process environment for building foreign extensions. A value provided by this hook overrules defaults provided by def_environment/2. In addition to changing the environment, this may be used to pass additional values to the environment, as in:
prolog_pack:environment('USER', User) :-
    getenv('USER', User).
Name- is an atom denoting a valid variable name
Value- is either an atom or number representing the value of the variable.
Source pack_upgrade(+Pack) is semidet
Try to upgrade the package Pack.
To be done
- Update dependencies when updating a pack from git?
Source pack_remove(+Name) is det
Remove the indicated package.
Source pack_property(?Pack, ?Property) is nondet
True when Property is a property of an installed Pack. This interface is intended for programs that wish to interact with the package manager. Defined properties are:
Directory into which the package is installed
Installed version
Full title of the package
Registered author
Official download URL
Package README file (if present)
Package TODO file (if present)

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

Source pack_list(Arg1)