finding out how many fields

[Fairlight]

Maybe a silly question, but I surely don't know the answer yet.  (And don't
call me Shirley.)  

Let's say I have an anonymous array overlaid on top of a generic lookup
starting at field 1 of the lookup.

I can do the lookup to any old table.  Is there a generic way to actually
determine how many fields are extant in the target table so that I never
try to access past that point in the array when handling fields from the
target table of the lookup?  I'm trying to avoid a situation where I try
accessing a field that's "out of bounds" (ie, doesn't exist).

mark->
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