FinBranchMutualWrong.err

MiniAgda by Andreas Abel and Karl Mehltretter
--- opening "FinBranchMutualWrong.ma" ---
--- scope checking ---
--- type checking ---
type  Nat : Set
term  Nat.zero : < Nat.zero : Nat >
term  Nat.suc : ^(y0 : Nat) -> < Nat.suc y0 : Nat >
type  Unit : Set
term  Unit.unit : < Unit.unit : Unit >
type  Prod : -(A : Set) -> ++(B : Set) -> Set
term  Prod.pair : .[A : Set] -> .[B : Set] -> ^(y0 : A -> B) -> < Prod.pair y0 : Prod A B >
type  Tree : Set
term  Tree.node : ^(numBranches : Nat) -> ^(y1 : VecTree numBranches) -> < Tree.node numBranches y1 : Tree >
{ VecTree Nat.zero = Unit
; VecTree (Nat.suc n) = Prod Tree (VecTree n)
}
error during typechecking:
checking positivity
/// polarity check ++ <= - failed