Just a small omission:  The SRFI currently does not specify:

- The behaviour of (real? z)     if z is not a complex number.
- The behaviour of (rational? x) if x is not a real number.
- The behaviour of (integer? q)  if q is not a rational number.

This can be corrected by changing the current spec:

  "If z is a complex number, then `(real? z)'
   is true if and only if `(zero? (imag-part z))' and
   `(exact? (imag-part z))' are both true."

to the following:

  "`(real? z)'
   is true if and only if
     z is a complex number
     and `(zero? (imag-part z))' and
         `(exact? (imag-part z))' are both true."

and similar for the other two predicates.

Andre