Overview

Ypsilon is the implementation of Scheme Programming Language, which conforms to the latest standard R⁶RS. It achieves a remarkably short GC pause time and the best performance in parallel execution as it implements "mostly concurrent garbage collection", which is optimized for the multi-core CPU system.

Ypsilon is easy to use as well as good for applications of any kind that require quick, reliable, and interactive data processing. It implements full features of R⁶RS and R⁶RS standard libraries including:

• arbitrary precision integer arithmetic
• rational number
• exact and inexact complex number
• implicitly phased library
• top-level program
• proper tail recursion
• call/cc and dynamic wind
• unicode
• bytevectors
• records
• exceptions and conditions
• i/o
• syntax-case
• hashtables
• enumerations

More libraries are included to support a wide variety of software development. Also it has built-in FFI which is easy to use. Please refer to the following files for FFI overview.

• example/gtk-hello.scm
• example/glut-demo.scm
• sitelib/ypsilon/glut.scm
• sitelib/ypsilon/gl.scm
• sitelib/ypsilon/ffi.scm

News

2008-12-23 Ypsilon 0.9.6-update3 released. This version fixed all bugs found and supports Windows XP/Vista(32bit), MacOSX(32bit), Linux(32/64bit) , FreeBSD(32/64bit).

2008-09-03 Ypsilon 0.9.6-update2 released. This is a bug fix release.

2008-08-15 Ypsilon 0.9.6-update1 released. This is a bug fix release.

2008-08-01 Ypsilon 0.9.6 released. This version fixed all bugs found in version 0.9.5.

Links

• Known bugs in current release
• Changes in latest version (trunk)
• Ypsilon development roadmap

• Xcode3: How to checkout latest source code from repository
• Windows: How to install Ypsilon to 'C:\Users\<UserName>\Ypsilon'
• Using binfmt_misc linux kernel module

Other Resources

Ypsilon has been developed as a fundamental technology for LittleWing Pinball Construction System.

• Ypsilon Wiki: http://www.littlewingpinball.net/mediawiki/index.php/Ypsilon
• Ypsilon Background Story: http://www.littlewingpinball.com/contents/en/ypsilon.html
• Draft documents (r6rs, socket, ffi, c-types): http://www.littlewing.co.jp/ypsilon/doc-draft/
• (Japanese) Ypsilon Background Story: http://www.littlewingpinball.com/contents/ja/ypsilon.html
• (Japanese) Ypsilon Wiki: http://www.littlewingpinball.net/mediawiki-ja/index.php/Ypsilon
• LittleWing Pinball Home: http://www.littlewingpinball.com/