Clafer tools and web tools 0.5.4 released: models in several files

  by Michał Antkiewicz, Oct 25, 2026

This release lets a Clafer model import other models, so that a model can be split into several files, for example, a design space and one file for each system that configures it (#100). All tools report errors with the file and the position in it, the editors for Visual Studio Code and Sublime Text 4 compile models and show the errors in place, and the compiler and chocosolver get several fixes. Binaries for Linux x86_64 are available from the Clafer tools binary distributions page.

Models in several files. A model imports other files in its first line, //# OPTIONS --import=design-space.cfr, or on the command line, clafer SystemA.cfr --import=design-space.cfr. The files are compiled together as one model, with one namespace; imports are followed transitively, each file once. A model and its imports can also be URLs, so a model can import a design space published on a server. Errors are given as file.cfr:line:column, in the file in which they are. See the Clafer Cheat Sheet for the details.

• clafer compiler, release pull request (0.5.4).
  • --import, also with http:// and https:// URLs; the options of all files are combined (e.g., the largest --maxint)
  • positions as file.cfr:line:column everywhere, also in a model of one file (previously line 3 column 5); the JSON output has the source positions of clafers and expressions, with their file, and the HTML output shows each file under its name
  • options that restrict imports for models that may come from anyone, as in the web tools: --import-root, --public-imports and --import-base; an imported file must be a .cfr file
  • group cardinality opt makes its children optional again, as in the language's definition
  • a group cardinality whose lower bound the children cannot reach (e.g., xor over no children) is an error instead of being silently unconstrained
  • fixes: comments no longer count in the indentation, clafer names with apostrophes (same') work with Alloy and Choco, comments are escaped in the HTML output, and unknown options in //# OPTIONS are an error instead of being ignored
• claferIG Alloy-based instance generator, release pull request (0.5.4).
  • uses clafer-0.5.4: --import, and the options in the model's //# OPTIONS apply
  • errors and the constraints of UnSAT cores give their file and position; the command c shows each file under its name, with the scope of the first clafer
  • instances show the clafers' names from the model
• chocosolver Choco-based instance generator, release pull request (0.5.4).
  • compiles a .cfr model with its imports, and shows the compiler's errors when it does not compile
  • fixes: references refined in subclafers of an abstract clafer (a model could have no instances), and a crash with parent.parent of an optional child of a nested abstract clafer
• claferwiki, release pull request (0.5.4).
  • uses clafer-0.5.4
  • fixes the model graphs behind HTTPS proxies and the syntax highlighting of code blocks
• Clafer for Visual Studio Code, release pull request (0.5.4).
  • compiles the model when it is saved, or with Clafer: Compile, and shows the errors in the model and in the Problems panel, also in imported files
  • Clafer: Instances (Alloy) and Clafer: Instances (Choco) run claferIG and chocosolver in a terminal
  • install the .vsix file from the GitHub release with code --install-extension clafer-syntax-0.5.4.vsix
• Clafer Tools for Sublime Text, release pull request (0.5.4), now for Sublime Text 4.
  • syntax highlighting that follows the Clafer grammar, and the compiler's errors shown in the model; double-click an error's position, or press F4, to open its file
  • the instance generators run in a Terminus tab; the tools are found on PATH
  • install or update Clafer Tools with Package Control
• Web tools: ClaferIDE, ClaferConfigurator, and ClaferMooVisualizer 0.5.4, with the common platform.
  • models can import other models: the tool's examples (--import=Examples/<file>.cfr) and .cfr files on public servers; a model opened from a wiki imports relative to its URL
  • messages give positions as model.cfr:line:column
  • fixed: the welcome window appears again, and the page no longer stays grayed out on the first visit

The Linux binary bundle contains clafer, claferIG with the optimized MiniSat solver, chocosolver.jar with a chocosolver launcher, and the Alloy jars. It runs on Linux x86_64 with glibc 2.39 or newer (Ubuntu 24.04, Debian 13, Arch Linux, Fedora) and needs Java 21 or newer. On Windows, use it through WSL.

Live demos (0.5.4): the Clafer Model Wiki, the Railway Wiki, the Traffic Lights Wiki, ClaferIDE, ClaferConfigurator, and ClaferMooVisualizer.

Note: a claferwiki page cannot import other models yet; it is compiled from its own code blocks. As before, reasoning (instance generation, configuration, optimization) works for the static subset of Clafer; behavioral models can be compiled to HTML.