huge-csv-6.go

func main() {
	// read metadata
	metadataChan := make(chan *line)
	go reader("metadata.csv", metadataChan)

	// read strength set IDs
	strengthSetChan := make(chan *line)
	go reader("strength_sets.csv", strengthSetChan)

	// join the two data streams
	augmentedLinesChan := make(chan *line)
	go joiner(metadataChan, strengthSetChan, augmentedLinesChan)

	// write computed lines
	fmt.Println("id,user_id,machine_id,circle_id,timestamp,strength_set_ids")
	for l := range augmentedLinesChan {
		fmt.Printf("%v,%v\n", l.id, l.restOfLine)
	}
}