Below is the reference implementation for SRFI-26 from

  http://srfi.schemers.org/srfi-26/cut.scm

adapted to Guile and passing all tests from

  http://srfi.schemers.org/srfi-26/check.scm

The reference implementation is public domain, and in my infinite
generosity I place my three lines of module declaration in the public
domain as well :)

-- 
Alex