How to define a function in ghci across multiple lines

Posted by Peter McGrattan on Stack Overflow See other posts from Stack Overflow or by Peter McGrattan
Published on 2010-05-17T00:16:14Z Indexed on 2010/05/17 0:20 UTC
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ghci

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haskell

I'm trying to define any simple function that spans multiple lines in ghci, take the following as an example:

let abs n | n >= 0 = n
          | otherwise = -n

So far I've tried pressing Enter after the first line:

Prelude> let abs n | n >= 0 = n
Prelude>           | otherwise = -n
<interactive>:1:0: parse error on input `|'

I've also attempted to use the :{ and :} commands but I don't get far:

Prelude> :{
unknown command ':{'
use :? for help.

I'm using GHC Interactive version 6.6 for Haskell 98 on Linux, what am I missing?

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