[Haskell-cafe] Language extensions

[Tomasz Zielonka]

On Mon, May 28, 2007 at 11:43:47AM +0100, Andrew Coppin wrote:
> - Chapter 2 is... puzzling. Personally I've never seen the point of 
> trying to check a program against a specification. If you find a 
> mismatch then which thing is wrong - the program, or the spec?

Knowing that one of them is wrong is already a very useful information,
don't you think?

> - Chapter 12 is incomprehensible (to me at least). "Fun with Phantom 
> Types" I've read it several times, and I still couldn't tell you what a 
> phantom type is...

Ironically, this chapter contains the following (at least the version
at http://www.informatik.uni-bonn.de/~ralf/publications/With.pdf):

     Of course, whenever you add a new feature to a language, you should
     throw out an existing one (especially if the language at hand is
     named after a logician). Now, for this chapter we abandon type
     classes - judge for yourself how well we get along without
     Haskell's most beloved feature.

You've found a language extension soulmate! ;-)

BTW, I really liked Ralf's chapter.

> There are some bits that are sort-of interesting but not really to do
> with anything I'm passionate about, and then there are bits that I
> can't comprehend...

Passionate... perhaps this is the root of the problem? Different people
are passionate about different things.

Best regards
Tomek