[Haskell-cafe] Mis-understanding something in Haskell interpretation

Bulat Ziganshin bulat.ziganshin at gmail.com
Tue Oct 3 15:26:57 EDT 2006

Hello Edward,

Tuesday, October 3, 2006, 9:44:27 PM, you wrote:

>     Couldn't match `Side' against `Int'
>     In the first argument of `sin', namely `angle'

> The source is below. Side is types as Float. My assumption was that
> Haskell would know how to convert the Int to a float and all would be
> well. I am I mistaken somewhere? The problem is with the last line.

yes, Haskell don't make automatic conversions because together with
bi-directional type inferring it will make a headache.

>         let  angle  = 1.0 * (360 / totalSides) *  currentSide  in

as Garret said, you should make conversions explicitly, hopefully the
'fromIntegral' function is enough in most cases

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at gmail.com

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