# CSFlex source generator provenance

This component is a modern .NET port of C# Flex 1.4, retrieved from the
authoritative SourceForge Subversion repository at revision 4:

https://svn.code.sf.net/p/csflex/code/trunk/

The scanner-generation core, generated specification scanner/parser, message
catalogue, and skeleton resources retain their upstream copyright notices.
The WinForms GUI and command-line front end were deliberately omitted. The
remaining core was adapted in July 2026 to run in memory and to expose a
Roslyn incremental source generator over `AdditionalFiles`.

C# Flex depends on the C# CUP runtime that upstream distributed as
`runtime.dll`. The compatibility sources in `CupRuntime/` were recovered from
that exact upstream binary and checked against the historical CUP.net source
archive `CUP-parser-generator-2003-12-06-19-53.zip` distributed by the
SourceForge `datagraph` project. They are included solely to support C# Flex's
upstream-generated grammar parser and retain the GPL-compatible CUP license in
`CupRuntime/LICENSE`.

The CSFlex port and its source-generator wrapper are distributed under
the terms in `COPYRIGHT` (GNU GPL version 2). As stated by upstream, code
generated by C# Flex inherits the copyright of its input specification; an
author-owned specification may therefore produce code used without
restriction. Generated Prexonite lexer code remains covered by the Prexonite
project's license, not by the generator's GPL.
