docs: function encode (value) {
  	var x = new Buffer(8);
  	var h, l;
  	
  	x.writeDoubleBE(value, 0);
  	
  	if(value < 0) {
  		x.writeUInt32BE((~x.readUInt32BE(0)) >>> 0, 0);
  		x.writeUInt32BE((~x.readUInt32BE(4)) >>> 0, 4);
  	} else {
  		/* non-negative; set the leading bit. */
  		x.writeUInt8(x.readUInt8(0) | 0x80, 0);
  	}
  	
  	return '\ue2f2' + enc85(x); 
  	/* 
  		The prefix is from the unicode private use area,
  		and is expected to not appear as the first character
  		of string key components. 2f2 is decimal 754, for
  		IEEE 754 (the floating point spec)
  	*/
  }