[Haskell-cafe] questions on lazy pattern, StateT monad

Wolfgang Jeltsch wolfgang at jeltsch.net
Wed Nov 23 07:26:14 EST 2005

Am Mittwoch, 23. November 2005 10:03 schrieb Fan Wu:
> [...]

> I'm puzzled over this line:
>     ~(a,s') <- lift (mplus m1' m2')

Why is this line in Monad.State.StateT?  Recently, we discussed that StateT 
does *not* use a lazy pattern here but that it should be changed to using 
one.  So where did you see this lazy pattern?

> [...]

Best wishes,

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