> The issue isn't with SRFIs as such, but with R7RS-small; there is no way
> for an implementation to communicate to its callers what features it
> does or does not support at or before compile time.  In SRFI 115, for
> example, there are various features that can be tested by cond-expand,
> but this is not very helpful, because there is no portable way to add a
> cond-expand feature.

The R7RS version of cond-expand supports (library (foo bar)) expressions
to test for a library that can be imported using (import (foo bar)).
Would it work in principle to put part of the procedures in a SRFI into
a separate library, or have I misunderstood how (library ...) works?