1. I see that the Book's second edition, as well as this site, shows the parameters of the SetPoint method to be

    region:SetPoint("point" [, relativeTo [, "relativePoint" [, xOffset [, yOffset]]]])

    i.e. parameters can be omitted only from the right. The first edition had instead

    region:SetPoint("point" [, relativeTo [, "relativePoint"]] [, xOffset, yOffset])

    which I think is accurate.

    The parameters are not independently optional, for instance

    region:SetPoint('CENTER', 'CENTER')

    throws the error "Couldn't find region named 'CENTER'", and providing only one of the coordinates causes a value of zero to be used for them both. But certainly

    region:SetPoint('CENTER', 20, 20)

    works fine, although the current documentation invalidates it.



    You are absolutely correct, thanks for pointing it out to me. This is due to a change from handwritten function signatures to auto-generated ones.. and I'll look to see if I can fix it.