Re: [Haskell-cafe] Hash table constructors return table in IO Monad. Why?

On Thu, May 12, 2011 at 9:22 AM, Stephen Tetley wrote:

The hashtable needs to be been created in IO, after that, think of the 'hashtable' as a analogous to a file handle. You have to pass it around to do anything with it - but the only things you can do with it are in IO.

The appropriate pure package to be using instead is unordered-containers.