Xanthos

F# wrapper library for JRA-VAN JV-Link API.

Overview

Xanthos provides a type-safe F# interface to the JRA-VAN JV-Link COM API, enabling developers to access Japanese horse racing data in a modern, functional programming style.

Features

• Type-safe API: Leverage F#'s type system for safer JV-Link interactions
• Stub mode: Test without COM dependencies on any platform
• Cross-platform: Core library works on Windows, macOS, and Linux (COM features Windows-only)

Text Encoding

• In-memory: Xanthos represents text as Unicode string (UTF-16).
• JV-Link input boundary: JV-Link returns CP932/Shift-JIS for “text”; Xanthos decodes it into string via Xanthos.Core.Text.
• Output boundary: console/log/file text is UTF-8 (no BOM). samples/Xanthos.Cli configures stdout/stderr accordingly.

Quick Start

Target net10.0-windows and run x64 with JV-Link 5.0 x64 installed and registered. The portable net10.0 target supports record parsing and deterministic tests.

open Xanthos

JvLink.withSession ConnectionOptions.Default (fun session ->
    JvLink.init "UNKNOWN" session
    |> Result.bind (fun () -> session |> JvLink.getVersion))
|> function
    | Ok version -> printfn "JV-Link %s" version
    | Error error -> eprintfn "%s: %s" error.Api error.Message

JvLink functions are curried with Session last; the owner releases COM and its STA on success, errors and consumer exceptions. Records provides the 38 official record parsers. The CLI selects real COM with --com and a deterministic backend with --stub.

See the functional API contract, CLI guide, event delivery and record migration.

Documentation

• SDK known limitations - Native communication errors and caller responsibilities
• API Reference - Auto-generated from XML documentation
• Architecture - Design documents

License

This project is licensed under the MIT License.