function mapArrayBufferViews(ary) {
  for (var i = 0; i < ary.length; i++) {
    var chunk = ary[i];
    if (chunk.buffer instanceof ArrayBuffer) {
      var buf = chunk.buffer;

      // if this is a subarray, make a copy so we only
      // include the subarray region from the underlying buffer
      if (chunk.byteLength !== buf.byteLength) {
        var copy = new Uint8Array(chunk.byteLength);
        copy.set(new Uint8Array(buf, chunk.byteOffset, chunk.byteLength));
        buf = copy.buffer;
      }

      ary[i] = buf;
    }
  }
}
* https://tools.ietf.org/html/draft-josefsson-eddsa-ed25519-03#section-5.2

EDDSA defines methods for encoding and decoding points and integers. These are
helper convenience methods, that pass along to utility functions implied
parameters.