Ah right, yes Shinn's fmt, that's the one. Would be interesting to see it run on vanilla Gambit and/or Black Hole.

2013/1/18 Taylor Venable <taylor@metasyntax.net>
On Wed, Jan 16, 2013 at 6:46 AM, Mikael <mikael.rcv@gmail.com> wrote:
More generally, this kind of thing would be done with a formatting library. I believe it remains for one tuned for Gambit yet to come into existence - there's a SchemeFmt library, something like this, out there that's cross-scheme, perhaps it could be adapted. Someone on the ML by the name Tanya I believe got it running on Gambit.

For what it's worth, Alex Shinn's fmt library [1] requires only slight modification to make up for missing string functions; also you can use the reference implementation of SRFI-48 [2] verbatim.

[1] http://synthcode.com/scheme/fmt/
[2] http://srfi.schemers.org/srfi-48/srfi-48.html

--
Taylor C. Venable
http://metasyntax.net/