[Haskell] Better Exception Handling

Lennart Augustsson lennart at augustsson.net
Thu Nov 25 14:39:54 EST 2004

Jules Bean wrote:
> By the same token, you can just stick the function strangeReadFile :: 
> FilePath -> String into the language. As long as it is memoized, always 
> returning the same value, it doesn't break beta-reduction. I call it 
> 'strange' because the time that the file is actually read is not 
> guaranteed, so if you read more than one file in your program, you have 
> no guarantee that you are reading a constant total state that actually 
> existed at any point in time.  (Before you think this sounds unbearably 
> horrible, there is at least one commercially sold RDBMS which has this 
> semantics on its select statements ;P)

It is also strange by the fact that strangeReadFile can very well be
different functions at different runs of the program.  That's why I
think such a function should be generated by the IO monad.  (If you
want it at all!)

	-- Lennart

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