bear wrote:

> With (read) capable of executing arbitrary code via quote,
> etc. it is entirely possible for (read) to encounter an
> error.  I want to know whether an error returned from (read)
> is one that was written and read, or one that prevented
> correct reading from occurring.

How is this different from expecting to read a list and getting #f
instead, and not being sure if the #f appeared as a literal in the input
stream or was generated by code called by the reader?

Do you want two different kinds of #f? Those that are generated and
those that are read?

Regards,

Alan
--
Dr Alan Watson
Centro de Radioastronomía y Astrofísica
Universidad Astronómico Nacional de México