I opened https://github.com/scheme-requests-for-implementation/srfi-171/pull/2
fixing all the problems I found by running the tests (I have not
really examined the implementation or stared long and hard at the
document to find anything more interesting). It makes it possible to
pass all three Scheme implementations. Not sure if we want to do like
that, anyway just fyi.

Also remaining problems are: tflatten (do we always call it or just
consider it a function variable like right now? seems inconsistent),
tpartition-all, and tindex (not implemented, should they?)
--
Duy