Ambiguous hyperkind

From The Twelf Project

An ambiguous hyperkind occurs in pathological cases like this:

a : type.

b = a : _ _ .

Twelf 1.7.1 (built 03/19/11 at 09:41:05 on gs6177)
a : type.
Error: 
Ambiguous reconstruction
Inferred: {x:`%A1%} kind
Omitted term has ambiguous hyperkind
Error: 
 1 error found

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