57. Go - Scopes

Package Level Scope:

- declaring variables outside main function.

- variables are accessible within other scripts within same package (folder)

Block Level Scope:

- declaring variables inside function curly braces

Exported and NotExported Names:

- Lower case variables/names are not accessible outside of package.

- Upper case variables/names are exported names and can be accessed outside of package.

Return Function with inner closure scope:

package main

import "fmt"

func printerr() func() int {

    x := 0

    return func() int {

        x++

        return x

    }

}

func main() {

    test1 := printerr()

    fmt.Println(test1())

    test2 := printerr()

    fmt.Println(test2())

    fmt.Println("TWO")

    fmt.Println(test2())

    fmt.Println(test2())

    fmt.Println(test2())

    fmt.Println(test2())

    fmt.Println("ONE")

    fmt.Println(test1())

}

// test1 is a printerr function with its own scope of x variable.

// test2 cannot access test1's variable x