[Haskell] more newbie questions regarding do syntax, mondic context & Data.HashTable

Christian Maeder maeder at tzi.de
Thu Dec 29 09:16:33 EST 2005

Hunter Kelly wrote:
> How can I get at the underlying value?  Can I only access it from
> within a "do" construct?

Yes, I'm afraid so

> Is there anyway to get at this function to return just True or False? 

No, (unless you use something unsafe that I would not recommend)

> Or has using something that uses an IO monad "polluted" everything
> else that depends on the answer?

Yes, that's the problem with Data.HashTable (and the reason for Data.Map 
and Data.Set).

Cheers Christian

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