Please disregard this message... Excerpts from Nicolas Pouillard's message of Mon Sep 01 14:30:09 +0200 2008:

Others types like NonNegative, NonZero have their constructor exported in Test.QuickCheck, the Positive constructor deserve the same :)

Sat Sep 6 14:23:22 CEST 2008 Nicolas Pouillard * Export the Positive constructor.

-- Nicolas Pouillard aka Ertai