src/bigi/lib/bigi.js
function bnpChangeBit(n, op) {
  var r = BigInteger.ONE.shiftLeft(n)
  this.bitwiseTo(r, op, r)
  return r
}
function bnpChangeBit(n, op) {
  var r = BigInteger.ONE.shiftLeft(n)
  this.bitwiseTo(r, op, r)
  return r
}
function bnpChangeBit ( n , op ) { var r = BigInteger . ONE . shiftLeft ( n ) this . bitwiseTo ( r , op , r ) return r }
(protected) this op (1<<n)
( protected ) this op ( 1<<n )