Richard wrote:
some are using Haskell for "systems programming", as a better C than C. some, including me, would like to see more of that, with Haskell or another pure functional language with an IO monad taking systems programmers away from the C and C++ communities.
That is good, I would probably call myself a C++ developer primarily, but Haskell + the IO monad is a much better choice (even better than Perl...) in most situations.
Hugs is completely useless for *that*.
Yes, it is, although it is great for testing the validity of one's Haskell programs.
for an example of Haskell as a better C than C, see Chak's Gtk+ bindings. to use them you must write your whole GUI in the IO monad in a style where the basic data structures and control structures closely resemble what you would write in C.
I have seen it, and it is a bit imperative in its style.
many Haskellers have a negative opinion of such heavy use of the IO monad, but in systems programming you need more control over when (relative to other interactions) your program performs an interaction with a file, network or UI resource than is available in Haskell without the IO monad.
I must confess that I belong to that "theoretical" group, although I am a systems programmer (i.e., developing real systems for real customers, paying real money). In my opinion, the use of categorical monads in a programming language is a brilliant intellectual achievement, combining the "pure" and "real" in programming, at least on paper... This is where the Haskellers divide: one group (me included) consider the hidden state in monads as falling back to imperative thought patterns. In some cases, as in IO, we need to have a state, obviously, but it would be beneficial if we could divide the logic into state independent (defined outside the monads) and state dependent code (defined within the monads; such as IO). It is a bit like some "C++" developers I meet, who consider themselves to develop in C++ just because they use "const" or "&" (reference): functional programming is about choice of language and choice of programming style. /David