Addendum:

 > inexact arrays must have inexact literals
I assume that is also inexact *real* literals.

 > complex arrays must have complex literals

Requiring complex literals sounds somewhat cumbersome if many of the
numbers I am inserting have zero imaginary part.

It would also make it a pain to copy-paste numbers.

Also, how would these restrictions interact with a hypothetical
quasiquoting numerical vector?

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 > I would leave it unspecified

I would at least add the following as a possible extension:

1. An exact number in an inexact real number array is converted as if
`inexact` was called on it.
2. A real number X in an complex number array is converted as if
`(make-rectangular (inexact X) 0.0)` was evaluated in that spot.
3. An exact complex number Z in a complex number array is converted as
if `inexact was called on it.

-- Peter McGoron