function inspect( chunk, idx ) {
		if ( cb ) {
			debug( 'Received a new chunk. Chunk: %s. Index: %d.', chunk.toString(), idx );
			return cb( log, chunk, idx );
		}
		if ( isBuffer( chunk ) ) {
			chunk = chunk.toString();
		}
		chunk = JSON.stringify( chunk );
		debug( 'Received a new chunk. Chunk: %s. Index: %d.', chunk, idx );
		log( 'Chunk: %s. Index: %d.', chunk, idx );
	}
Callback invoked upon receiving a new chunk.

@private
@param {*} chunk - received chunk
@param {NonNegativeInteger} idx - chunk index
@returns {void}