[Haskell] ST Monad and all that

Wolfgang Jeltsch wolfgang at jeltsch.net
Fri Jul 8 07:02:38 EDT 2005

Am Freitag, 8. Juli 2005 12:48 schrieb Srinivas Nedunuri:
> Hello, in trying to understand how to use the ST Monad I've come across
> references to a bewildering variety of related types such as STRefs,
> STArrays, MutVar, ArrayRef, IORef, IOArray, ArrRef, etc. the list goes on.
> Is there a place where I can get a comprehensive explanation of what's
> what? Its a bit fustrating trying to figure out how these concepts relate
> to each other by reading snippets of information on different web sites and
> papers (e.g. "State in Haskell").
> Thanks for your help

Hello Srinivas,

some of these identifiers are just outdated and replaces by more current ones.  
For example, as far as I know, STRef is the new name for MutVar.  You might 
want to have a look at GHC's library documentation at


although this might not give enough information for you.

Best wishes,

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