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An Oops! in Level 2 text

Vladik, P1788

Really someone should have pulled me up short about wid(xx) (width of an interval) in the Level 2 draft text. I had written
   wid(xx) returns the same value as 2 ∗ rad(xx)

This is quite wrong, e.g. in 3-digit decimal, if xx = [.234,.235] then mid(xx), if we follow the roundTiesToEven rule of motion 37, will be m=.234, and rad(xx) will be .00100. My recipe above gives width w=.00200 but surely the only sensible result is .00100, the actual width. 

So IMO the correct recipe is
   wid(xx) returns the smallest F-number ≥ the mathematical width xhi-xlo.

Vladik: what is the Level 2 width of Empty? I would be happy with

  NaN, on the grounds that it is genuinely undefined; 
or
  -oo, on the grounds that wid(xx) = (sup xx) - (inf xx), and when
       xx=Empty, one has sup xx = -oo and inf xx = +oo.

John Pryce