-- | union of Signatures
-- or do I have to care about more things here?
sigUnion :: Sign -> Sign -> Result Sign
sigUnion s1 = Result [Diag Debug "All fine sigUnion" nullRange]
    . Just . unite s1
sigUnion :: Sign -> Sign -> Result Sign
sigUnion s1 = Result [Diag Debug "All fine sigUnion" nullRange]
    . Just . unite s1
sigUnion s1 = Result [Diag Debug "All fine sigUnion" nullRange]
    . Just . unite s1