Unprocessed form tail error from CL:LOOP

[pamoroso]

The Medley implementation of Common Lisp loop doesn't support nested iterations and returns the error Loop form tail (...) remained unprocessed. for such clauses. A test case is available.

This was discovered when evaluating the compatibility of Medley Common Lisp with ANSI Comon Lisp as part of issue #609, specifically by testing the condition system code of the book Practical Common Lisp as described in discussion #1613.

[tfeb]

See my comment to #1613 which probably belongs here: loop doesn't do nested iteration and I think the implementation is correct with regards to #1613: the code is wrong in other words. I may be wrong in that case but certainly loop does not do nested iteration.

[pamoroso]

Thanks, I renamed the issue "Unprocessed form tail error from CL:LOOP".

[tfeb]

@pamoroso While I think (same caveat as before!) that the error message is unhelpful it is, I think correct: presumably what it's saying is 'I was a state where I expected an x but I saw a y and gave up'