type K = enum ka,kb type A = object case kind: K of ka: adata:int of kb: bdata:string proc a():A = A(kind:ka) var an = a() an.adata = 5 echo an.kind, an.adata #an.kind = kb #an.bdata = "6" #Causes exception! reset(an) an.kind = kb an.bdata = "6" echo an.kind, an.bdata