This library is provided to make it easier to reason about software versions, in particular require that that hosting Prolog system is of the right version and provides the features required by the library or application.

To be done

- Not only provide a minimal version but a more version ranges, exclude certain versions, etc.

- More features and better messages to help the user resolving problems.

 require_prolog_version(+Required:atom, +Features:list) is det

Claim that the running Prolog version is at least version Required and provides the requested Features. Required is an atom or string that provides the version as

Major.Minor[[.Patch][[-GitRev],-GitHash]]]

Example strings are '8.5', '8.5.0', '8.5.0-50', '8.5.0-69-gad38e8ad8`. The last two require fetching the sources from git or using the Windows daily builds.

Features is a list of required or preferred features. Individual features are:

warning(Feature)

Only print a warning instead of throwing an error.

threaded

Demand support for multi-threading

rational

Demand native support for rational numbers

library(Lib)

Demand library(Lib) to be present. Thde library not being there may indicate an incomplete installation. For example library(pce) to demand xpce graphics support.

Flag

Demand current_prolog_flag(Flag, true) to be true.

FlagValue

If FlagValue is Flag(Value), demand current_prolog_flag(Flag, Value) to be true.

Errors

- prolog_version(Required, Found)

- prolog_feature(Feature))