Lambda the Ultimate

This may be obvious to many of you, but it got me thinking:

module Main where

data Z = X Int | Y Int

xy z = case z of
         X a -> "X"
         Y a -> "Y"

x = X 0

y = Y 1

Above Haskell program works as expected: (xy x) outputs X and (xy y) outputs Y. So although Haskell uses static typing, at times it needs to do type checking at runtime? Any studies on overhead of runtime type checking in languages employing static vs. "dynamic" typing?

Mike Shapiro, Purpose-Built Languages, ACM Queue vol. 7, no. 1, February 2009.

Mike Shapiro from Sun Microsystems examines the evolution of what he calls "purpose-built languages" (essentially domain-specific languages). Shapiro discusses the way that such languages have often been a key part of the development of larger software systems, and describes how many of them have sprung into existence and evolved without formal design. In particular, he traces the evolution of the adb debugger language. As Shapiro says:

The debugger tale illustrates that a little purpose-built language can evolve essentially at random, have no clear design, no consistent grammar or parser, and no name, and yet endure and grow in shipping operating systems for more than 40 years. In the same time period, many mainstream languages came and went into the great beyond... For purpose-built languages, a deep connection to a task and the user community for that task is often worth more than clever design or elegant syntax.

The same article also appeared in the April 2009 issue of Communications of the ACM.

Hello All,

I have no idea, how should we deal with spam or other inappropriate content.

I miss somehow a button to signal quickly such content. Some other forum engines have such things. I don't know the implementation details.

Regards.

PS. There are two spam topics now, the node 3301 (a klonopin spam) and the node 3300 (a viagra spam).

I have a couple of Logo turtle graphics examples that I need to reproduce in high resolution. any suggestions which software I can use? (I am lazy, so I prefer something that can execute the logo directly though translating to other languages should be trivial; it uses logo variables and list handling primitives).

So is there any high resolution freely available logo implementation out there?