[Haskell-beginners] question about pattern guards

[Daniel Trstenjak]

> What am I missing?

You can combine booleans by '||', but 'Just n <- x' doesn't result to a
boolean.

You can use '<|>' from 'Control.Applicative' to get the desired behavoir.

f x y
   | Just _ <- x <|> y = 1
   | otherwise           = 2

Greetings,
Daniel
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