The do notation in this instance yields a nice advantage: if you want to switch to a different monad to encapsulate failure you will meely need to swap out the type signature and your function will need no further work.
I'm a somewhat experienced coder but I am relatively new to Haskell.
I've got a question about whether a usage of do notation is idiomatic,
or whether it's better to use pattern matching.
I've got two functions which take an input and return Maybe SomeType.
If either returns Nothing, I also want to return Nothing. If they both
return something, then I'll return something unrelated.
With do notation, I can write something like this:
do
foo <- callFoo x
bar <- callBar x
return (baz)
Alternatively, there's a straightforward pattern match. After binding
foo, bar in a couple of where clauses:
case (foo,bar) of (Just x, Just y) -> baz
_ -> Nothing
So which approach is more idiomatic, do you think?
Thanks,
- Matthew
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