src/bigi/lib/bigi.js
function bnpCopyTo(r) {
  for (var i = this.t - 1; i >= 0; --i) r[i] = this[i]
  r.t = this.t
  r.s = this.s
}
function bnpCopyTo(r) {
  for (var i = this.t - 1; i >= 0; --i) r[i] = this[i]
  r.t = this.t
  r.s = this.s
}
(protected) copy this to r