Re: [Haskell-cafe] Newbie question on Haskell type

In GHC you can do this:

import Data.Typeable

isString :: (Typeable a) => a -> Bool isString x = typeOf x == typeOf (undefined::String)

Why do you want this? It's not the kind of operation one does very often in Haskell. Huong Nguyen wrote:

Hi all,

I want to write a small functionto test whether an input is a String or not. For example,

isString::(Show a) =>a ->Bool This function will return True if the input is a string and return False if not

Any of you have idea about that? Thanks in advance

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