Doubts...

[Hal Daume III]

In short, these need to be in a file.  Take a look at YAHT (yet another
haskell tutorial) which is under development and see if that answers any
of your questions...if not, PLEASE let me know so I can update the
tutorial so it does answer your questions.

The tutorial is available off my web page http://www.isi.edu/~hdaume as a
DVI, PS or PDF.

 - Hal

--
Hal Daume III

 "Computer science is no more about computers    | hdaume@isi.edu
  than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume

On Fri, 26 Jul 2002, Pedro L. P. Dias wrote:

> Dear Professor:
> 
> My name is Carlos Alexandre Grimaldi.  I'm engineering student at Federal University of Rio de Janeiro, Brazil.  I began my studies in Haskell, and I have some doubts which I report here.
> I'm very gratefully if you could help me.
> I'm following a book I downloaded from Internet: "A Gentle Introduction to Haskell, Version 98".  Following this, I face some problems:
> 
> - "inc :: Integer -> Integer" don't work
> 
> - "inc n = n+1" don't work too;
> 
> - "data Bool = False | True" also...;
> 
> - "data Color = Red | Green | Blue | Indigo | Violet" also fails.
> 
> I thought that this commands and definitions must be inside a program, and don't at prompt "prelude>".  So, I opened other book, also downloaded from Internet: "The Hugs 98 User Manual", and I tryed:
> 
> "module Fact where
> fact :: Integer -> Integer
> fact n = product [1..n]"
> 
> thinking that would be created a file "Fact", in which the definitions for "fact" would work.  But this also yield an error...  So, I ask you:
> 
> - is necessary the creation of a file where that definitions could work?
> 
> - is this file a ".hs"?
> 
> - how can I create a file like this?  Which command or editor?
> 
> - or, if I wrong, why that examples don't work?
> 
> Thank you very much for your help.
> Best regards,
> Carlos A. Grimaldi.
>