code: function makeConcat(chunkType) {
  	switch (chunkType) {
  	case BUFFER:
  		return (a, b) => Buffer.concat([a, b]);
  	default:
  		return (a, b) => {
  			// console.log('[%d, %d]', a.length, b.length);
  			const t = new Uint8Array(a.length + b.length);
  			t.set(a);
  			t.set(b, a.length);
  			// console.log('%d: %s', t.length, new Buffer(t).toString('utf8'));
  			return t;
  		};
  	}
  }
docs: Makes function to concat two byte chunks.
  @param  {Boolean} [chunkType] Specifies type of input chunks.
  @return {Function} The function to concat two byte chunks.