[Haskell-cafe] Re: Function to cast types

Anonymous Anonymous wrote:

Hello,

I'm new to haskell, I'm wondering how can you write a function that will do the following:

fromIntToString :: Int -> String

this is a cast function to cast an Int to a String. I know such function exist, however let's assume it didn't exist. How would I write such function?

I have no Idea, but this one works: intOfChar c | c >= '0' && c <= '9' = fromEnum c - fromEnum '0' intOfChar _ = undefined intOfString = sum . map (uncurry (*)) . zip (map (10^) [0..]) . map intOfChar . reverse ...assuming that 0..9 are consecutive in the Char Enum, which they are. Reading intOfString backwards, you get: reverse the string, change each digit to its integer value, pair it up with the right power of 10, multiply those pairs, and finally sum everything up. You can replace map f . zip with zipWith f , but that doesn't change much. -- (c) this sig last receiving data processing entity. Inspect headers for copyright history. All rights reserved. Copying, hiring, renting, performance and/or quoting of this signature prohibited.