[Haskell-beginners] Why is there no notion of a one-tuple (e.g., a '([])' as opposed to a '[]') in Haskell?

ajb at spamcop.net ajb at spamcop.net
Thu Sep 25 01:11:57 EDT 2008

G'day all.

Quoting Ben Lippmeier <Ben.Lippmeier at anu.edu.au>:

>> Perhaps more crucially, it's hard to see where such a thing would
>> be useful.
> IORef, and ML's ref types are sort of one element tuples.

I used to do a fair bit of hash consing myself.  I'm definitely sold on

But they're not quite the same thing as 1-tuples.  The fact that you need
to go through a monad in Haskell shows why they are different.

Andrew Bromage

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