Haskell modules: hidden names and ghci
I'm trying to export just a subset of names from a Haskell module, but ghci happily lets me access even the hidden names.
module Hiding (shown, calc) where
calc = shown * hidden
shown :: Int
shown = 3
hidden :: Int
hidden = 2
But when trying this in ghci I get:
Prelude> :l Hiding.hs
[1 of 1] Compiling Hiding ( Hiding.hs, interpreted )
Ok, modules loaded: Hiding.
*Hiding> hidden
2
What am I doing wrong?
(Edit: for what it's worth, I'm using ghci 6.12.3 on开发者_开发百科 Arch Linux)
It looks like GHCi is loading your module for you to inspect it, i.e. putting you in the scope of the module. Two hints at that are the prompt *Hiding>
and the fact that you accessed the hidden function.
Edit:
End there it is: http://www.haskell.org/ghc/docs/latest/html/users_guide/interactive-evaluation.html#id3045728
It looks to me like you've done the right thing. If you attempt to reference that module from another module I'll bet hidden
refuses to work. Could be that GHCI is all-knowing :)
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