From this question
How do I use a (generic) vector in go?
I tried to create a new vector but the compiler says it is undefined:
$ 6g -V
6g version release.r60.3 9516
$ cat > vectest.go <<.
> package main
>
> import vector "container/vector"
> import "fmt"
>
> func main() {
> vec := vector.New(0);
> buf := make([]byte,10);
> vec.Push(buf);
>
> for i := 0; i < vec.Len(); i++ {
> el := vec.At(i).([]byte);
> fmt.Print(el,"
");
> }
> }
> .
$ 6g vectest.go
vectest.go:7: undefined: vector.New
What might be wrong ?
The container/vector package has been deleted. Slices are better. SliceTricks: How to do vector-esque things with slices.
I revised your convertToLCD code to have better performance: 5,745 ns/op versus 19,003 ns/op.
package main
import (
"fmt"
"strconv"
)
const (
lcdNumerals = `
_ _ _ _ _ _ _ _
| | | _| _||_||_ |_ ||_||_|
|_| ||_ _| | _||_| ||_| _|
`
lcdWidth = 3
lcdHeight = 3
lcdLineLen = (len(lcdNumerals) - 1) / lcdWidth
)
func convertToLCD(n int) string {
digits := strconv.Itoa(n)
displayLineLen := len(digits)*lcdWidth + 1
display := make([]byte, displayLineLen*lcdHeight)
for i, digit := range digits {
iPos := i * lcdWidth
digitPos := int(digit-'0') * lcdWidth
for line := 0; line < lcdHeight; line++ {
numeralPos := 1 + lcdLineLen*line + digitPos
numeralLine := lcdNumerals[numeralPos : numeralPos+lcdWidth]
displayPos := displayLineLen*line + iPos
displayLine := display[displayPos : displayPos+lcdWidth]
copy(displayLine, string(numeralLine))
if i == len(digits)-1 {
display[displayLineLen*(line+1)-1] = '
'
}
}
}
return string(display)
}
func main() {
fmt.Printf("%s
", convertToLCD(1234567890))
}
Output:
_ _ _ _ _ _ _ _
| _| _||_||_ |_ ||_||_|| |
||_ _| | _||_| ||_| _||_|
It's true there is no vector.New in r60.3, but rather than patch up this code, you should learn the new append function. It made the vector package unnecessary, and in fact the package was removed some time ago from the weekly releases.