How to use the bitcore-lib-cash.util function in bitcore-lib-cash

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var BufferUtil = bitcore.util.buffer;
var BloomFilter = require('../../bloomfilter');
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;

/**
 * Request peer to send inv messages based on a bloom filter
 * @param {BloomFilter=} arg - An instance of BloomFilter
 * @param {Object} options
 * @extends Message
 * @constructor
 */
function FilterloadMessage(arg, options) {
  Message.call(this, options);
  this.command = 'filterload';
  $.checkArgument(
    _.isUndefined(arg) || arg instanceof BloomFilter,

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var BufferUtil = bitcore.util.buffer;

/**
 * Request peer to clear data for a bloom filter
 * @extends Message
 * @constructor
 */
function FilterclearMessage(arg, options) {
  Message.call(this, options);
  this.command = 'filterclear';
}
inherits(FilterclearMessage, Message);

FilterclearMessage.prototype.setPayload = function() {};

FilterclearMessage.prototype.getPayload = function() {
  return BufferUtil.EMPTY_BUFFER;

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var utils = require('../utils');
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;
var BufferReader = bitcore.encoding.BufferReader;
var BufferWriter = bitcore.encoding.BufferWriter;

/**
 * @param {Array=} arg - An array of addrs
 * @param {Object=} options
 * @extends Message
 * @constructor
 */
function AddrMessage(arg, options) {
  Message.call(this, options);
  this.command = 'addr';
  $.checkArgument(
    _.isUndefined(arg) ||
      (Array.isArray(arg) &&

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;

/**
 * @param {Transaction=} arg - An instance of Transaction
 * @param {Object} options
 * @extends Message
 * @constructor
 */
function TransactionMessage(arg, options) {
  Message.call(this, options);
  this.command = 'tx';
  this.Transaction = options.Transaction;
  $.checkArgument(
    _.isUndefined(arg) || arg instanceof this.Transaction,
    'An instance of Transaction or undefined is expected'
  );

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var utils = require('../utils');
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;
var BufferUtil = bitcore.util.buffer;
var BufferReader = bitcore.encoding.BufferReader;

/**
 * A message in response to a ping message.
 * @param {Number} arg - A nonce for the Pong message
 * @param {Object=} options
 * @extends Message
 * @constructor
 */
function PongMessage(arg, options) {
  Message.call(this, options);
  this.command = 'pong';
  $.checkArgument(
    _.isUndefined(arg) || (BufferUtil.isBuffer(arg) && arg.length === 8),

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var utils = require('../utils');
var BufferReader = bitcore.encoding.BufferReader;
var BufferWriter = bitcore.encoding.BufferWriter;
var _ = bitcore.deps._;
var $ = bitcore.util.preconditions;

/**
 * Sent in response to a `getheaders` message. It contains information about
 * block headers.
 * @param {Array} arg - An array of BlockHeader instances
 * @param {Object=} options
 * @param {Array=} options.headers - array of block headers
 * @param {Function} options.BlockHeader - a BlockHeader constructor
 * @extends Message
 * @constructor
 */
function HeadersMessage(arg, options) {
  Message.call(this, options);
  this.BlockHeader = options.BlockHeader;
  this.command = 'headers';
  $.checkArgument(

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var utils = require('../utils');
var BufferReader = bitcore.encoding.BufferReader;
var BufferWriter = bitcore.encoding.BufferWriter;
var $ = bitcore.util.preconditions;

/**
 * Query another peer about block headers. It can query for multiple block hashes,
 * and the response will contain all the chains of blocks starting from those
 * hashes.
 * @param {Object=} options
 * @param {Array=} options.starts - Array of buffers or strings with the starting block hashes
 * @param {Buffer=} options.stop - Hash of the last block
 * @extends Message
 * @constructor
 */
function GetheadersMessage(arg, options) {
  Message.call(this, options);
  this.command = 'getheaders';
  this.version = options.protocolVersion;
  if (!arg) {

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var BufferUtil = bitcore.util.buffer;
var BloomFilter = require('../../bloomfilter');
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;

/**
 * Request peer to send inv messages based on a bloom filter
 * @param {BloomFilter=} arg - An instance of BloomFilter
 * @param {Object} options
 * @extends Message
 * @constructor
 */
function FilterloadMessage(arg, options) {
  Message.call(this, options);
  this.command = 'filterload';
  $.checkArgument(
    _.isUndefined(arg) || arg instanceof BloomFilter,
    'An instance of BloomFilter or undefined is expected'
  );

'use strict';

var bitcore = require('bitcore-lib-cash');
var $ = bitcore.util.preconditions;
var BufferUtil = bitcore.util.buffer;
var BufferReader = bitcore.encoding.BufferReader;
var BufferWriter = bitcore.encoding.BufferWriter;
var _ = bitcore.deps._;

/**
 * A constructor for inventory related Bitcoin messages such as
 * "getdata", "inv" and "notfound".
 * @param {Object} obj
 * @param {Number} obj.type - Inventory.TYPE
 * @param {Buffer} obj.hash - The hash for the inventory
 * @constructor
 */
function Inventory(obj) {
  this.type = obj.type;
  if (!BufferUtil.isBuffer(obj.hash)) {

'use strict';

var Message = require('../message');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib-cash');
var utils = require('../utils');
var BufferUtil = bitcore.util.buffer;
var BufferWriter = bitcore.encoding.BufferWriter;
var BufferReader = bitcore.encoding.BufferReader;
var $ = bitcore.util.preconditions;
var _ = bitcore.deps._;

/**
 * Request peer to add data to a bloom filter already set by 'filterload'
 * @param {Buffer=} data - Array of bytes representing bloom filter data
 * @param {Object=} options
 * @extends Message
 * @constructor
 */
function FilteraddMessage(arg, options) {
  Message.call(this, options);
  this.command = 'filteradd';
  $.checkArgument(
    _.isUndefined(arg) || BufferUtil.isBuffer(arg),
    'First argument is expected to be a Buffer or undefined'
  );