docs: function mpn_pack(words) {
  	var k = words.length, n = mpn_new(Math.ceil(k * 32 / 31)), w, wr = 0, l = 0, lr = 31;
  	for (var i = 0, j = 0;;) {
  		if (wr == 0) {
  			if (++i > k) {
  				if (l != 0) {
  					n[j++] = l >>> lr;
  				}
  				return n;
  			}
  			w = words[k - i], wr = 32;
  		}
  		var s = Math.min(wr, lr);
  		l = l >>> s | (w & (1 << s) - 1) << 31 - s, w >>>= s;
  		if ((lr -= s) == 0) {
  			n[j++] = l;
  			l = 0, lr = 31;
  		}
  		wr -= s;
  	}
  }