Labelled types question

[Simon Peyton-Jones]

The code should not be able to see "c".  Nor the data constructor "A".
You don't say which Haskell implementation you are using.

Simon

| -----Original Message-----
| From: Andre W B Furtado [mailto:awfurtado@homelink.com.br]
| Sent: 09 September 2002 19:15
| To: haskell@haskell.org
| Subject: Labelled types question
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| Suppose I have a labelled type 'A' defined like the following one:
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| module Test (
|  A (b)
| )
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| where
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| data A =3D A
|  { b :: Int,
|    c :: Int
|  }
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| I am exporting only 'A(b)', so why the following code "can see" 'c' ?
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| module Main where
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| import Test
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| main :: IO ()
| main =3D print (c (A {c=3D3,b=3D2}))
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| PROMPT> 3
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| If Test exports only 'A', not 'A(b)', the I get the expected
compilation
| problem:
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| ERROR "label.hs" (line 6): "c" is not a selector function/field name
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| Am I missing something obvious here?
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| Thanks,
| -- Andre
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