law gg
lawful-arrays@0.1.0.0 · proof_index.bend:116
import lawful-arrays@0.1.0.0/proof_index.bend as ProofIndex
import Base
import lawful-arrays@0.1.0.0/defs.bend as D
import lawful-arrays@0.1.0.0/proof_tree.bend as P
116law gg:
117 for -T: Data
118 for +d: Nat
119 for +t: P.Tree<T>
120 for +n: U32
121 for +i: U32
122 for +z: Bool
123 for +hf: {D.full(T, P.fromT(T, t), d) == True{} : Bool}
124 for +hn: {U32.to_nat(n) == Nat.pow(2n, d) : Nat}
125 for +hi: {Nat.is_lt(U32.to_nat(i), Nat.pow(2n, d)) == True{} : Bool}
126 for +hz: {U32.is_lt(i, U32.shr(n)) == z : Bool}
127 {Some{Pair.snd(Array<T>, T, Array.get.go(T, P.fromT(T, t), n, i, z))}
128 == List.get(&2, T, D.view(T, P.fromT(T, t)), U32.to_nat(i)) : Maybe<&2, T>}