There is a long-standing bug in the SRFI 1 specification that couldn't
be fixed because we didn't have an erratum process.  The definitions of
`any`, `every`, and `list-index` specify that the predicates must return
a boolean result, i.e. `#t` or `#f`.  This has never been the case:
all known implementations accept ordinary predicates that can return
any object other than `#f` to mean "true".  The words "and returning a
boolean result" should be removed from each definition.

Here's a paragraph for the Status section:

Erratum:  The procedures `any`, `every`, and `list-index` accept
predicates that can return any value other than `#f` to represent "true".

--
John Cowan          http://www.ccil.org/~cowan        xxxxxx@ccil.org
In my last lifetime, I believed in reincarnation;
in this lifetime, I don't.  --Thiagi