[Haskell-beginners] defining functions in ghci

[Amy de Buitléir]

You need to put "let" in front of any sort of definition in GHCI.

let double x = x + x

2010/1/25 Joe Van Dyk <joe at fixieconsulting.com>:
> Prelude> double x = x + x
> <interactive>:1:9: parse error on input `='