Bradley Lucier <xxxxxx@math.purdue.edu> writes:

> Thanks.  Now in the will package I get the error:
>
> [bradley-luciers-power-mac-g4-cube:~/Desktop/srfi-77/implementation]
> bjlucier% scheme48
> Welcome to Scheme 48 1.3 (made by root on Sat Oct 22 22:26:09 CDT 2005)
> Copyright (c) 1993-2005 by Richard Kelsey and Jonathan Rees.
> Please report bugs to scheme-48xxxxxx@s48.org.
> Get more information at http://www.s48.org/.
> Type ,? (comma question-mark) for help.
>> ,config ,load packages.scm
>>  ,in r6rs/will
> r6rs/will> ,open srfi-34
> r6rs/will> (load "complex-test.scm")
> complex-test.scm
> <whole lot of stuff omitted>
> (+ +#{Fx 0}+#{Fx 0}i +#{Fx 0}+#{Fx 0}i)        =>         +#{Fx 0}+#
> {Fx 0}i
> (- +#{Fx 0}+#{Fx 0}i +#{Fx 0}+#{Fx 0}i)        =>         +#{Fx 0}+#
> {Fx 0}i
> (* +#{Fx 0}+#{Fx 0}i +#{Fx 0}+#{Fx 0}i)        =>         +#{Fx 0}+#
> {Fx 0}i
> (/ +#{Fx 0}+#{Fx 0}i +#{Fx 0}+#{Fx 0}i)        =>
> Error: contagion error
>        ("ERROR")
>        ("ERROR")
>        #{Procedure 9414 (=/2 in generic-arithmetic/will)}
>        (&error)
>
> ???

This error is due to

(/ (make-rectangular (r5rs->number 0) (r5rs->number 1)) (r5rs->number 0))

raising an exception.  Your program converts the result into
("ERROR"), which your program then feeds to =.  (In PRINT-NUMBER,
expression (= x x).)  The error message is admittedly obscure---it
means that there's no way to convert the arguments of = into suitable
numbers.

> On a separate note, when I change (display x) to (display (number-
>>string x)) to get rid of the #{Fx 0}, etc., I get
>
> r6rs/will> (load "complex-test.scm")
> complex-test.scm
> (+ +
> Error: wrong number of arguments
>        ('#{Procedure 9676 (number2string in numbers-to-strings)} '#
> {Fx 0} '#{Fx 10})

Bug.  Replace the first three code lines in number2string by:

(define (number->string x . more)
  (if (null? more)
      (number2string x (r5rs->integer 10) #f)

--
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla