Re: Misplaced syntactic keyword defvar

[Dirk Herrmann]

Bill Schottstaedt wrote:

> Now (in Saturday's CVS Guile) I get this:
>
> guile> (define defvar #f)
> guile> (set! defvar define)
> guile> (set! defvar define)
>
> Backtrace:
> In standard input:
>    4: 0* (set! #<primitive-builtin-macro! define> define)
>
> standard input:4:1: In expression (set! #<primitive-builtin-macro! 
> define> define):
> standard input:4:1: Unbound variable: #<primitive-builtin-macro! define>
> ABORT: (unbound-variable)

I have submitted a hopefully working fix this time. But, just as a reminder:

 (define defvar #f)
 (set! defvar define)

is not allowed according to R5RS. Neither is

 (set! define #f)

In R5RS you don't find the concept that define and other syntactic keywords
have a location to which you can assign. The same holds for the concept that
for every syntactic keyword there is a corresponding macro object. Both of
these are guile extensions, but their use should probably be avoided.

Best regards
Dirk