[Haskell] ST vs State

Donald Bruce Stewart dons at cse.unsw.edu.au
Wed May 30 05:01:51 EDT 2007

> Hello dear Haskellers,
> Could someone be kind and explain with some detail what are the
> differences between the two monads:
> Control.Monad.ST
> And
> Control.Monad.State
> ?
> They are both meant to model stateful computation but they are not the
> same monad. The first one represents state with in place update?

Very very different.

The former is for filling memory blocks in a pure manner, the latter
models threaded state.

-- Don

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