Pack or Package?
"Pack" and "Package" seem to be used alternatingly. However. as i understand it:
- Package: An official SWI-Prolog add on
- Pack: An unofficial SWI-Prolog add-on
This page is about the latter.
It is unclear what this means exactly:
"Note that the toplevel directory of the archive can be ., <pack> or <pack>-<version>."
I suppose this is about naming the directory, but a directory can never be named `.`.
Name of the pack. This must be provided. Must consists of ASCII characters that can always appear in filenames.
This depends on the underlying filesystem of course. A
: is valid on ext4, but not on NTFS for example. Special characters SHOULD be avoided but characters beyond ASCII SHOULD be allowed. What will our Chinese friends say?
Please limit to ASCII to avoid problems with character encodings.
That's an unreasonable requirement. We have been in unicode world 25+ years now. It would be much better to demand that pack.pl be encode in UTF-8. Or do it as for XML: have an encoding marker at the start of the file:
% Encoding: UTF-8
That would be pretty straightforward.
Also, I suppose the Title is a string or atom?
Why not just state that semantic version https://semver.org/ should be implemented?
A normal version number MUST take the form X.Y.Z where X, Y, and Z are non-negative integers, and MUST NOT contain leading zeroes. X is the major version, Y is the minor version, and Z is the patch version. Each element MUST increase numerically. For instance: 1.9.0 -> 1.10.0 -> 1.11.0.
But this also allows the following:
A pre-release version MAY be denoted by appending a hyphen and a series of dot separated identifiers immediately following the patch version. Identifiers MUST comprise only ASCII alphanumerics and hyphens [0-9A-Za-z-]. Identifiers MUST NOT be empty. Numeric identifiers MUST NOT include leading zeroes. Pre-release versions have a lower precedence than the associated normal version. A pre-release version indicates that the version is unstable and might not satisfy the intended compatibility requirements as denoted by its associated normal version. Examples: 1.0.0-alpha, 1.0.0-alpha.1, 1.0.0-0.3.7, 1.0.0-x.7.z.92, 1.0.0-x-y-z.–.
Build metadata MAY be denoted by appending a plus sign and a series of dot separated identifiers immediately following the patch or pre-release version. Identifiers MUST comprise only ASCII alphanumerics and hyphens [0-9A-Za-z-]. Identifiers MUST NOT be empty. Build metadata MUST be ignored when determining version precedence. Thus two versions that differ only in the build metadata, have the same precedence. Examples: 1.0.0-alpha+001, 1.0.0+20130313144700, 1.0.0-beta+exp.sha.5114f85, 1.0.0+21AF26D3—-117B344092BD.
are interesting but to really make this work, one needs the tools (similar to the RPM database and the
rpm command) and the associated documentation of behaviour & semantics. I don't think this is implemented? (Or maybe one could just piggyback onto existing package managers? In any case, it's a mountain of work)
All must be atom
AT least for now,
pack.pl must be a stream of compound terms that will be read by read_term/3. No comments allowed.
In the source code of
prolog_pack.pl, we find these typing requirements for the terms:
pack_info_term(name(atom)). % Synopsis pack_info_term(title(atom)). pack_info_term(keywords(list(atom))). pack_info_term(description(list(atom))). pack_info_term(version(version)). pack_info_term(author(atom, email_or_url)). % Persons pack_info_term(maintainer(atom, email_or_url)). pack_info_term(packager(atom, email_or_url)). pack_info_term(home(atom)). % Home page pack_info_term(download(atom)). % Source pack_info_term(provides(atom)). % Dependencies pack_info_term(requires(dependency)). pack_info_term(conflicts(dependency)). % Conflicts with package pack_info_term(replaces(atom)). % Replaces another package pack_info_term(autoload(boolean)). % Default installation options
Version: Exact? Match?
Can I have a version string '1.0' and name the package with '1.0.0'? Must the match be exact?
Might be of interest to add history information to the pack.