Hey Maciek,
On Fri 14 Nov 2008 11:38, "Maciek Godek" <[EMAIL PROTECTED]> writes:
> Hey all yoh!
> Is there any "official" way to check whether or not
> a function returns a (specified) value?
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)'.
> but I find it kinda surprising that these are not available
> by default in the system.
Odd, yes. We inherit this oddity from Scheme.
Andy
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