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I'm trying to invert a string in go but I'm having trouble handling the characters. Unlike C, GO treats strings as vectors of bytes, rather than characters, which are called runes here. I tried to do some type conversions to do the assignments, but so far I could not.

The idea here is to generate 5 strings with random characters of sizes 100, 200, 300, 400 and 500 and then invert their characters. I was able to make C work with ease, but in GO, the language returns an error saying that it is not possible to perform the assignment.

 func inverte() 
 var c = "A"
 var strs, aux string

 rand.Seed(time.Now().UnixNano())
 // Gera 5 vetores de 100, 200, 300, 400, e 500 caracteres
 for i := 1; i < 6; i++ 
 strs = randomString(i * 100)
 fmt.Print(strs)

 for i2, j := 0, len(strs); i2 < j; i2, j = i+1, j-1 
 aux = strs[i2]
 strs[i2] = strs[j]
 strs[j] = aux
 
 

As you correctly identified, go strings are immutable, so you cannot assign to rune/character values at given indices.

Instead of reversing the string in-place one must create a copy of the runes in the string and reverse those instead, and then return the resulting string.

For example (Go Playground):

func reverse(s string) string 
 rs := rune(s)
 for i, j := 0, len(rs)-1; i < j; i, j = i+1, j-1 
 rs[i], rs[j] = rs[j], rs[i]
 
 return string(rs)


func main() 
 fmt.Println(reverse("Hello, World!"))
 // !dlroW ,olleH
 fmt.Println(reverse("Hello, 世界!"))
 // !界世 ,olleH

There are problems with this approach due to the intricacies of Unicode (e.g. combining diacritical marks) but this will get you started.