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[t x <txrev319 AT gmail.com>]

Hi,

  Here is my minimal failure example:

https://gist.github.com/anonymous/df6b5d1cf5a81592ea4d

  I'm trying to build a variant of "<-" of the Maybe Monad where I can pull out either a Z or a Bool.

  However, I'm getting an error about some "product" rather than a myOpt.

  What am I doing wrong, and how do I fix this?

Thanks!