On 2010-10-30 07:07, Mark Spezzano wrote:
Hi,
Can somebody please explain exactly how the monad functions "sequence" and
"sequence_" are meant to work?
I have almost every Haskell textbook, but there's surprisingly little
information in them about the two functions.
From what I can gather, "sequence" and "sequence_" behave differently
depending on the types of the Monads that they are processing. Is this correct? Some concrete
examples would be really helpful.
sequence [m1,m2,m3,m4,...] = do
x1 <- m1
x2 <- m2
x3 <- m3
x4 <- m4
...
return [x1,x2,x3,x4,...]
sequence_ [m1,m2,m3,m4,...] = do
m1
m2
m3
m4
...
return ()
Cheers,
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