Re: [Haskell-cafe] Mixed-type arithmetic, or type coercion

Hi

Arithmetic operators in haskell appear to require their operands to have the same type. How can I do arithmetic between operands of different types?

You probably don't want to.

Alternatively, how do I coerce a value from being an Int to being a Double?

You ask Hoogle: http://haskell.org/hoogle/?q=Integer+-%3E+Double The answer is fromInteger/toInteger as required.

calc :: Int -> Double -> Double calc count weight = fromInteger (toInteger count) * weight

toInteger promotes the Int to an Integer, fromInteger then converts that to a Double. Thanks Neil