[Haskell-cafe] Vertical tabs in source code and other obscure chars

[Brian Hulley]

Hi,
In the Haskell98 report at http://haskell.org/onlinereport/lexemes.html 
section 2.2 has the rule:

    whitechar -> newline | vertab | space | tab | uniWhite

Does anyone know what a vertical tab is supposed to do?
Is there any reason to allow them as whitespace? (Does anyone in the 
universe actually use them?)

Thanks, Brian.
-- 
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Yet still phantoms restless for eras long past,
congealed in the present in unthought forms,
strive mightily unseen to destroy us.

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