Lambda the Ultimate

i have got a gmail
thanx guys

The apps are built using PHP and a simple XML-vocabulary based DSL called XNHTML.

As I've been saying for a long time here and elsewhere, it's all about programmability these days, and as the Ning folks realise DSLs are a very good technique for achieving end-user programmability.

Seems to me they could have gone the extra mile, and eliminated the need for PHP altogether, but I guess that would be asking for too much...

Even in a lazy language like Haskell, lifted boolean operators like 'and' are not commutative. What I mean is that they're commutative only as long as bottom is not involved. In that case, for example, 'and' and 'flip and' are not interchangeable. This causes problems in certain applications like trying to simulate certain cyclic logic circuits. To a great extent you can avoid these problems by carefully thinking about which input to 'and' you want to use, but I'm interested in designing a system where this is not necessary.

I've just finished coding up a system that has a commutative and. It consist of two parts: a new 'and' called 'land' that uses Maybe Bool as its data type and a discipline for programming with 'land' that requires you to iterate until you find a fixed point before returning a result.

I'm looking for some references to papers, books, web sites, etc. that might help me understand more about this topic and not reinvent the wheel any further than I already have. I'm also interested in the generalized version of this topic, i.e. beyond boolean operators: "when conventional laziness just isn't lazy enough." I've done some Googling but haven't seem to hit upon the "magic words."