Re: Unspecified?

[Jon Wilson]

Andy Wingo wrote:
> Yes and no; R5RS has this to say:
>
>     If the value of an expression is said to be "unspecified," then the
>     expression must evaluate to some object without signalling an error,
>     but the value depends on the implementation; this report explicitly
>     does not say what value should be returned.
>
> In practice, in all situations in which R5RS defines a result as
> unspecified, those values will be `eq?' to `(if #f #f)'.
For Guile, yes.  But an R5RS conforming Scheme might well return a 
unique value for every expression whose value is unspecified.  (display 
"unspecified") might return 5, or "unspecified", or a pink and white 
unicorn whale.  But Guile is kind to us, and always returns the same 
value as is returned by (if #f #f), namely, *unspecified*.

I know you already know all this, Andy.  I'm just running my mouth off.
Regards,
Jon