golang generics and constraint interface
Golang has support for generic since 1.18. To see a simple example of how we can use it, check out the following codes:-
We declare generics right next to the function name declaration using [T number] as shown below:-
package main
import (
"fmt"
)
type Number interface {
int | float32 | float64
}
func PrintNumbers[T Number](t []T) {
for _, v := range t {
fmt.Println(v)
}
}
func PrintValue[T any](t []T) {
for _, v := range t {
fmt.Println(v)
}
}
func main() {
PrintValue([]int{1, 2, 3, 4})
PrintValue([]string{"1", "2", "3"})
PrintNumbers([]int{1, 2, 3, 4})
// constraint are not satisfied here
//PrintNumbers([]string{"1", "2", "3"})
}
Then we have generics for struct - as you can see here
type Box[T any] struct {
Value T
}
func GetValue[T any](value T) {
fmt.Println(value)
}
func main() {
box := Box[int]{Value: 4}
fmt.Println("", box.Value)
GetValue(box.Value)
}
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