New subject: loop problem

10 May 2014

      Stuart A. Kurtz schreef op 10-5-2014 18:02:
...
Dear Roelof,
...
Thanks , it's working now like this :
loop :: Int -> IO ()
loop n = do
     if n <= 100
     then do
         putStrLn (show n );
         putChar ' ';
         putStrLn (show (n * n )) ;
         loop (n + 1);
     else
        return () ;
main :: IO ()
main = loop 1
But the outcome looks like this:
1
    1
2
    4
You're getting good advice, but this strikes me as extraordinarily unidiomatic Haskell -- it reads like a translated C program. Fixing it doesn't eliminate that sense.
Why not this?
main :: IO ()
     main = putStr . unlines . map (unwords . map show . (\n -> [n,n^2])) $ [1..100]
Peace,
Stu
Like I said to another person . Im now following this course: 
https://www.fpcomplete.com/school/starting-with-haskell/basics-of-haskell

But I get the feeling it's not a good one. Maybe find another 
tutorial/course where I can learn it the right way and do a lot of 
exercises so I can see if I understand things right. I learn the best by 
doing things and not only read about it.

Roelof

Re: [Haskell-cafe] loop problem

Roelof Wobben

Alexander Berntsen

Roelof Wobben

Ian Ross

Sam Caldwell

Mike Meyer

Roelof Wobben

Mike Meyer

Stuart A. Kurtz

Alexander Berntsen

Brandon Allbery

Alexander Berntsen

Stuart A. Kurtz

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