fails.v

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Fail Check (tt 1).The command has indeed failed with message:
Illegal application (Non-functional construction): 
The expression "tt" of type "unit"
cannot be applied to the term
 "1" : "nat"
Check (tt 1).Illegal application (Non-functional construction): 
The expression "tt" of type "unit"
cannot be applied to the term
 "1" : "nat"