Meh, everyone's beat mine. 

#!/usr/bin/runhaskell
import IO
main=do t<-(hGetContents stdin);putStrLn$show$foldl max 0$map length$l
+ines t

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The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re: Golf: Length of longest line in a file by Fletch
in thread Golf: Length of longest line in a file by toolic

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