Beginning Haskell: "not in scope" Unprecedented error

Posted by user1071838 on Stack Overflow See other posts from Stack Overflow or by user1071838
Published on 2011-11-29T17:47:55Z Indexed on 2011/11/29 17:49 UTC
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scope

So I just started learning Haskell, and this (http://learnyouahaskell.com) nifty book is giving a lot of help. So yesterday I wrote in a text file

    doubleMe x = x + x

and saved it as double.hs. So after saving that I open up my command prompt, CD to the right folder, type in "ghci" to get haskell started, and then type in

    >doubleMe 5
    10

and everything seems to work. Now today, I do the same thing and this happens (actual copy paste from command line) . . .

    C:\Users\myName\haskell>ghci
    GHCi, version 7.0.3: http://www.haskell.org/ghc/  :? for help
    Loading package ghc-prim ... linking ... done.
    Loading package integer-gmp ... linking ... done.
    Loading package base ... linking ... done.
    Loading package ffi-1.0 ... linking ... done.
    Prelude> :l double.hs
    [1 of 1] Compiling Main             ( double.hs, interpreted )
    Ok, modules loaded: Main.
    *Main> doubleMe 5

    <interactive>:1:1: Not in scope: `doubleMe'

So basically, everything was working fine, but now haskell can't find the function I wrote in double.hs. Can anyone tell what is going on? I'm pretty lost and confused. This is just a guess but does it have to do with *Main at all? Thanks for the help.

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