1/1: Building LCase (LCase.idr)
Error: While processing right hand side of foo. There are 0 uses of linear name y. 

LCase:11:11--13:41
 11 |     = let 1 test = the MyNat $ case z of
 12 |                         MyZ => MyZ
 13 |                         (MyS k) => MyS z

Suggestion: linearly bounded variables must be used exactly once.