Go language scope (Range)
Go in the language range keyword is used for for iterate the array in the loop, slice , channel or collection ( map ). Itreturns the values corresponding to the index of the element in arrays and slices and in the collection key-value.
Example
package main
import "fmt"
func main() {
//This is how we use range to sum a slice.
Using arrays is similar to this
nums := []int{2, 3, 4}
sum := 0
for \_, num := range nums {
sum += num
}
fmt.Println("sum:", sum)
//Using range on an array will pass in two variables: index and value.
We did not need to use the ordinal of the element in the above example,
so we omitted it with the
blank character "_". Sometimes we do need to know its index.
for i, num := range nums {
if num == 3 {
fmt.Println("index:", i)
}
}
//range can also be used on key value pairs in maps.
kvs := map[string]string{"a": "apple", "b": "banana"}
for k, v := range kvs {
fmt.Printf("%s -> %s\\n", k, v)
}
//Range can also be used to enumerate Unicode strings. The first parameter is the index of the character,
and the second parameter is the character (Unicode value) itself.
for i, c := range "go" {
fmt.Println(i, c)
}
}
The output of the above instance is as follows:
sum: 9
index: 1
a -> apple
b -> banana
0 103
1 111