[Ur] stateful structure?

[Marc Weber]

> Is it possible to write a monad in ur?
Of course it is. Search the mailinglist. There has been some discussion
about it because there are some "sealed" monads meaning you can't
reuse the definition - but you could duplicate them.

> hash in ur?
ur has more powerful features: type checked dictionaries.

If you want to find out whether ur provides hash like structures
I'd grep for "option" because there must be a function returning either
a value of a key or nothing.

If it does not exist it can be implemented easily using data types.
Eg have a look at Haskell's source and the "Map" type:
http://haskell.org/hoogle/?hoogle=Map
You can click on the "Source" links.

I don't know exactly whether ur ships with such an implementation. Would
be trivial to write though.

Marc Weber