Round braces are used for grouping, it's necessary to avoid ambiguity since
a function can be defined with more than one argument. When using case you
don't have this potential ambiguity, so don't need the parentheses. Tuples
are more of a special case in the grammar that isn't closely related to
this.
safeHead p = case p of
[] -> Nothing
x : xs -> Just x
On Friday, October 24, 2014, Rohit Sharma
All,
I started learning haskell very recently and have a question on the pattern matching style for lists.
In the below snippet i.e. "(x:xs)" why do we went with round braces and not square? I know we are using cons that tells this is not a tuple but would it not make more sense to write something like [x:xs] instead of (x:xs), i thought round braces was used for pair/tuples?
safeHead [] = Nothing safeHead (x:xs) = Just x
Thanks, Rohit