Documentation bug? {Numeric,GHC.Float}.floatToDigits: requires a non-negative argument

The library report doesn't seem to mention this, but giving floatToDigits a 
negative number leads to nonsensical answers:

Prelude> Numeric.floatToDigits 10 (-3.1415)
([-32,5,8,5],0)

Now, this probably makes perfect sense, but shouldn't the doco mention the 
fact that floatToDigits requires a non-negative number?  It does for other 
functions that require non-negative arguments.

A

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Andy Moran                                         Ph. (503) 626 6616, x113
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