Haskell: get first element of the list

You may think that, it is very simple; I can call head function on a list and return the value. Be cautious head function is a partial function, it thrown an exception on empty list.

Prelude> head []

*** Exception: Prelude.head: empty list

To make it work fine, we need to check for list emptiness. Following function return ‘Just element’, if the list is not empty, else Nothing.

getFirstEle list = if not (null list) then Just (head list) else Nothing

Prelude> let getFirstEle list = if not (null list) then Just (head list) else Nothing
Prelude> 
Prelude> getFirstEle []
Nothing
Prelude> getFirstEle [1, 2, 3]
Just 1
Prelude> getFirstEle "Hare Ram"
Just 'H'
Prelude> 

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