How to determine the number of characters in a string?

Using the utf8.RuneCountInString() function from the unicode/utf8 package.

import (
	"fmt"
	"unicode/utf8"
)

func main() {
	str := "Привет, мир!"
	count := utf8.RuneCountInString(str) // Counts the number of runes (characters)
	fmt.Println(count)                 // Output: 12
}