Hello,

I've added the maintainers e-mail address to the discussion and have 
added "[PATCH]" to the subject to make it more clear that there is a 
patch file attached.

I tested a version that uses a `seq-map-while`, but it only made a 
difference when the sequence of values to copy to the existing sequence 
was longer than 100 elements, which I would guess is a less common use case.

Thank you,
Earl