Hi Daniel, On Tue 20 Oct 2009 04:44, Julian Graham <jool...@gmail.com> writes:
> (syntax-case x () > ((foo . rest) > (datum->syntax #'rest 'foo))) > > ...you get an error if `foo' is expanded without anything to bind to > `rest': I downloaded Petite Chez Scheme today and tried this out. I also got an error. I suspect you would get an error with ikarus or other psyntax-using implementations as well. > What's the right thing to do here? Do you just have to be careful > with what you do with pattern variables that might end up getting > bound to no arguments? R6RS isn't totally clear on the topic, but, > for what it's worth, the same code seems to work in MzScheme. I think for now the story would just be to be careful, unless you are in possession of a +12 Cloak of Psyntax Hack :) Andy -- http://wingolog.org/
