Re: Transcribe-file handles bad input badly

A
> > (defun transcribe-file (in-file out-file
> >                               &optional (package :common-lisp-user)
> >                                         (prettyp t))
>
> >   (when (string-equal in-file out-file)
> >     (error "Input and output file names are the same."))
> >   (let ((*package* (find-package package)))...
>
>So I guess *package* gets bound to nil if there is (one would hope!) no
>package named package. This seems to make transcribe-file go away and
>not come back.


Binding *package* to NIL could be considered a bad idea

:-)

For instance, this hangs

(let ((*package* nil)) (intern "FOO"))

and this hangs

(let ((*package* nil)) (error "Bad package: ~A" nil))

but interestingly, this does not:

(let ((*package* nil)) (error "OOPS"))

Since *PACKAGE* can only legitimately be bound to a package,
with presumably undefined consequences resulting if not,
code which binds it must insure that this is so.

So to fix TRANSCRIBE-FILE

(let* ((p (find-package package))
         (*package* (or (and (packagep p) p)) (error "Not a known package: 
~A" package)))
         ...



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