structure LocalDefs = LocalDefs;
structure Calculation = Calculation;
structure SkipProof = SkipProof;
LP = Base +
rules
pi_sb "[| A:*; !!x. x:A ==> B(x):[] |] ==> Prod(A,B):[]"
lam_sb "[| A:*; !!x. x:A ==> f(x):B(x); !!x. x:A ==> B(x):[] |]
==> Abs(A,f) : Prod(A,B)"
end