[r6rs-discuss] [Formal] Expand the set of self-evaluating datums
sperber at informatik.uni-tuebingen.de
Mon Jan 29 07:57:59 EST 2007
John Cowan <cowan at ccil.org> writes:
> Peter Gavin scripsit:
>> I don't think the empty list should be self-evaluating. No other list
>> in scheme is self-evaluating, so why should the empty one be?
> Because it can be neither syntax (which must have a keyword) nor a function call
> (which must have at least one form). Making () self-evaluating also represents
> a return to Lisp tradition; it would be interesting to know why it was made
> *not* self-evaluating in RRRS.
I believe the reason is that otherwise, parens always mark a compound
form where the first subform somehow identifies the operator.
Generally, Scheme seems to often favor uniformity over convenience.
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla
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