Bug: (for X previous Y ...) does not check existence of Y

[Attila Lendvai]

> Iterate silently ignores "for ... previous" clauses that reference undefined
> variables, e.g,
>
> (iter (repeat 2)
>    (for x previous y initially 0)
>    (collect x))
>
> returns (0 0).
>
>
> A patch to fix the bug is attached. Can someone apply it please.


pushed. thanks for the report and the fix!

-- 
• attila lendvai
• PGP: 963F 5D5F 45C7 DFCD 0A39
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