Haskell : "Parse error in pattern:" when creating a maximum' function

Question

So I am trying to implement a maximum function but for some reason I am getting a parse error on the last line "mymax x:y:ys = ..... " . What is the reason for that error? Thanks!

mymax :: Ord a=>[a]->Maybe a
mymax [] = Nothing
mymax [x] = Just x
mymax x:y:xs = if (x < y) 
            then mymax(y:xs) 
            else mymax(x:xs)

Possible duplicate of Haskell: Parse error in pattern

Chris Martin
– Chris Martin

2017-09-06 07:53:14 +00:00
Commented Sep 6, 2017 at 7:53 — Chris Martin
– Chris Martin, Commented Sep 6, 2017 at 7:53

fjarri · Accepted Answer · 2013-09-18 04:42:03Z

3

You're missing the parentheses:

mymax (x:y:xs) = if (x < y) 
                 ...

answered Sep 18, 2013 at 4:42

fjarri

9,74645 silver badges52 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

bheklilr · Accepted Answer · 2013-09-18 04:42:28Z

2

Put parenthesis around x:y:xs

mymax (x:y:xs) = ...

answered Sep 18, 2013 at 4:42

bheklilr

54.2k6 gold badges112 silver badges167 bronze badges

Collectives™ on Stack Overflow

Haskell : "Parse error in pattern:" when creating a maximum' function

2 Answers 2

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related