On Mon, Oct 17, 2011 at 2:57 PM, Georg Brandl <g.brandl@gmx.net> wrote:
I can believe that others see the "given" semantics as the natural order of things. This is probably why Haskell has both "let x = y in z" and "z where x = y" constructs to locally bind names, but there it fits well with the syntax, while in the case of Python, the "given: suite" feels somewhat out of place; we really have to think hard before adding new syntax -- one more thing that the "casual" users Nick mentioned have to grok.
Yeah, that's a large part of why I now think the given clause needs to be built on the same semantics that we already use internally for implicit out of order evaluation (i.e. decorators, comprehensions and generator expressions), such that it merely exposes the unifying mechanic underlying existing constructs rather than creating a completely new way of doing things. I'm also interested in any examples people have of APIs that engage in "decorator abuse" to get the kind of declarative API I'm talking about. it would be nice to be able to explain classes in terms of the same underlying construct as well, but that gets rather messy due to the fact that classes don't participate in lexical scoping and you have the vagaries of metaclasses to deal with. Cheers, Nick. -- Nick Coghlan | ncoghlan@gmail.com | Brisbane, Australia