def h.at1_shl
import bend-kit-collections@0.1.4.1/PROOF.bend as PROOFimport Base
2010def h.at1_shl(n: Nat, w: Word(n), e: {h.at1(n, w) == True{} : Bool})
2011 -> {h.at1(n, Word.shl(n, w)) == True{} : Bool}:
2012 match n:
2013 case 0n:
2014 {==}
2015 case 1n+p:
2016 match w:
2017 case WCon{b, t}:
2018 h.at1_put(p, t, b, e)