Here is a simple way to read the lines of a text file in Go without using the io package. You will need the fmt package. Create a file read.go with contents
package main
import "fmt"
func main() {
lines := make([]string, 0)
var line string
var err error
for {
_, err = fmt.Scanln(&line)
if err != nil {
break
}
lines = append(lines, line)
}
fmt.Println(len(lines))
}
Now consider the file text.txt with contents
line1
line2
line3
line4
At the command line, use
cat ./text.txt | go run read.go
The output is 4.
Similarly, we can read an array from a line. This is how I figured out how to do it; there is most likely a better way of doing this. Start with a file array.go:
package main
import "fmt"
func main() {
x := make([]int, 0)
var y int
var err error
for {
_, err = fmt.Scan(&y)
if err != nil {
break
}
x = append(x, y)
}
fmt.Println(x)
}
and a file nums.txt:
1 2 3 4 5 6 7 8 9 10 11
At the command line, use
cat ./nums.txt | go run array.go
The output is [1 2 3 4 5 6 7 8 9 10 11].