Euclid.Kontur

Imported from goswinr/Euclid.Kontur (AGENTS.md). Install upstream with npx skills add goswinr/Euclid.Kontur. Copyright stays with the author.

Notes for coding agents

Euclid.Kontur is an F# library. It targets .NET (net6.0 and net472) and also compiles to JavaScript and TypeScript with Fable, so everything has to stay Fable compatible. Read DESIGN.md first: it holds the reviewed design, the pipeline and the reasons behind every decision.

Conventions

• Follow the coding standards of the Euclid repository: PascalCase types and members, camelCase functions, 4 spaces, XML docstrings on every public member, errors through Euclid.EuclidErrors.fail.
• Hot paths use raw float[] and int[] with a separate count, never ResizeArray, tuples or struct records. Fable compiles raw numeric arrays to typed arrays.
• Index those arrays with Arr.get arr i and Arr.set arr i v from Src/Arr.fs, never with arr.[i]. Fable compiles arr.[i] into a bounds checked library call that dominated the profile under Node, see DESIGN.md section 6. ResizeArray indexing outside the hot paths keeps the plain indexer.
• No int64, BigInteger, Span, stackalloc, ArrayPool or Array.Sort(keys, items). They are not available on Fable .
• Visitor callbacks are inline members with [<InlineIfLambda>] parameters. State a visitor needs lives in fields, not in captured let mutable locals.
• Tests use Scriptorium (Quill for the DSL, Nib for the assertions) and run unchanged on .NET and on Node:
  • dotnet run --project ./Test/Test.fsproj
  • cd Test && npm install && npm test

Cloud sessions

In cloud containers the .NET SDK is not preinstalled. .claude/hooks/session-start.sh installs it asynchronously, so dotnet may not be on PATH in the first minute. Wait and retry.

CHANGELOG.md must not use wrapped bullets

Src/Euclid.Kontur.fsproj derives the package version from CHANGELOG.md with Ionide.KeepAChangelog.Tasks 0.3.3. Its parser throws on a bullet that wraps onto an indented continuation line, and that failure aborts the whole build. Keep one bullet on one line, however long, and use nested - sub-bullets for structure.