def one_le_shift

bend-collections-laws-crypto@1.0.0.0 · proofs/crypto/poly1305/arith.bend:114

import Base
import bend-collections-laws-crypto@1.0.0.0/spec/lib/common.bend as C
import bend-collections-laws-crypto@1.0.0.0/proofs/lib/logic.bend as L
import bend-collections-laws-crypto@1.0.0.0/proofs/math/typed/width.bend as WW

114# 1 <= 2^k
115def one_le_shift(+k: Nat, +one: Nat, +h1: {one == 1n : Nat}) -> {Nat.is_le(1n, C.shift(k, one)) == True{} : Bool}:
116  L.subst(Nat, z => {Nat.is_le(z, C.shift(k, one)) == True{} : Bool}, one, 1n, h1, WW.shift_ge(k, one))