def tree_con

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/blake/blake3/tree.bend:137

import Base
import bend-collections-laws-crypto@1.0.0.0/src/crypto/blake/blake3/types.bend as T
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/logic.bend as L
import bend-collections-laws-crypto@1.0.0.0/spec/lib/common.bend as SC
import bend-collections-laws-crypto@1.0.0.0/spec/crypto/blake/blake3.bend as S

137def tree_con(+g: Nat, +xs: List<&2,T.Out>, +ne: {S.is_nil(xs) == False{} : Bool}) -> {S.tree(1n+g,xs) == S.join(S.tree(g,SC.take(T.Out,xs,SC.pow2(g))),S.tree(g,SC.drop(T.Out,xs,SC.pow2(g))),S.is_nil(SC.drop(T.Out,xs,SC.pow2(g)))) : T.Out}:
138  match xs:
139    case Nil{}: Empty.absurd({S.tree(1n+g,Nil{}) == S.join(S.tree(g,SC.take(T.Out,Nil{},SC.pow2(g))),S.tree(g,SC.drop(T.Out,Nil{},SC.pow2(g))),S.is_nil(SC.drop(T.Out,Nil{},SC.pow2(g)))) : T.Out},L.true_false(ne))
140    case Con{+x,+r}: {==}