[Rd] (PR#14066) model.frame error with formula=~1 and na.action=na.fail

[Sebastian Meyer]

Thank you for your rapid bug fix and for your instructive comments on my
bug report.

> this is not 'model.frame error', nor even reported by R as such.

Of course you are right, but I thought that a bug report on model.frame
would probably reach more attention further providing a more motivating
frame for the bug than just writing that
complete.cases(as.data.frame(matrix(,150,0)))
would not work, and I was absolutely sure that you would be able to
track down the source of the problem.

>> data(iris)
>
> That line is unnecessary: 'iris' is a visible object in package
> 'datasets'.

Ok. I was not sure about this and just wanted to be on the save side to
offer a reproducible example working in a maximum variety of R sessions.

Best regards and thank you very much for your intense development of R,
   Sebastian Meyer