Punteros en Golang

Los punteros en el lenguaje de programación Go o Golang es una variable que se utiliza para almacenar la dirección de memoria de otra variable. Los punteros en Golang también se denominan variables especiales. Las variables se utilizan para almacenar algunos datos en una dirección de memoria particular en el sistema. La dirección de memoria siempre se encuentra en formato hexadecimal (comenzando con 0x como 0xFFAAF, etc.).

¿Cuál es la necesidad de los punteros? 

// Golang program to demonstrate the variables
// storing the hexadecimal values
package main
 
import "fmt"
 
func main() {
 
    // storing the hexadecimal
    // values in variables
    x := 0xFF
    y := 0x9C
     
    // Displaying the values
    fmt.Printf("Type of variable x is %T\n", x)
    fmt.Printf("Value of x in hexadecimal is %X\n", x)
    fmt.Printf("Value of x in decimal is %v\n", x)
     
    fmt.Printf("Type of variable y is %T\n", y)
    fmt.Printf("Value of y in hexadecimal is %X\n", y)
    fmt.Printf("Value of y in decimal is %v\n", y)   
     
}

// Golang program to demonstrate the declaration
// and initialization of pointers
package main
 
import "fmt"
 
func main() {
 
    // taking a normal variable
    var x int = 5748
     
    // declaration of pointer
    var p *int
     
    // initialization of pointer
    p = &x
 
        // displaying the result
    fmt.Println("Value stored in x = ", x)
    fmt.Println("Address of x = ", &x)
    fmt.Println("Value stored in variable p = ", p)
}

// Golang program to demonstrate
// the nil value of the pointer
package main
 
import "fmt"
 
func main() {
 
        // taking a pointer
    var s *int
     
    // displaying the result
    fmt.Println("s = ", s)
}

// Golang program to demonstrate
// the use of type inference in
// Pointer variables
package main
 
import "fmt"
 
func main() {
 
    // using var keyword
    // we are not defining
    // any type with variable
    var y = 458
     
    // taking a pointer variable using
    // var keyword without specifying
    // the type
    var p = &y
 
    fmt.Println("Value stored in y = ", y)
    fmt.Println("Address of y = ", &y)
    fmt.Println("Value stored in pointer variable p = ", p)
}

// Golang program to demonstrate
// the use of shorthand syntax in
// Pointer variables
package main
 
import "fmt"
 
func main() {
 
    // using := operator to declare
    // and initialize the variable
    y := 458
     
    // taking a pointer variable using
    // := by assigning it with the
    // address of variable y
    p := &y
 
    fmt.Println("Value stored in y = ", y)
    fmt.Println("Address of y = ", &y)
    fmt.Println("Value stored in pointer variable p = ", p)
}

// Golang program to illustrate the
// concept of dereferencing a pointer
package main
  
import "fmt"
  
func main() {
  
    // using var keyword
    // we are not defining
    // any type with variable
    var y = 458
      
    // taking a pointer variable using
    // var keyword without specifying
    // the type
    var p = &y
  
    fmt.Println("Value stored in y = ", y)
    fmt.Println("Address of y = ", &y)
    fmt.Println("Value stored in pointer variable p = ", p)
 
    // this is dereferencing a pointer
    // using * operator before a pointer
    // variable to access the value stored
    // at the variable at which it is pointing
    fmt.Println("Value stored in y(*p) = ", *p)
 
}

// Golang program to illustrate the
// above mentioned concept
package main
  
import "fmt"
  
func main() {
  
    // using var keyword
    // we are not defining
    // any type with variable
    var y = 458
      
    // taking a pointer variable using
    // var keyword without specifying
    // the type
    var p = &y
  
    fmt.Println("Value stored in y before changing = ", y)
    fmt.Println("Address of y = ", &y)
    fmt.Println("Value stored in pointer variable p = ", p)
 
    // this is dereferencing a pointer
    // using * operator before a pointer
    // variable to access the value stored
    // at the variable at which it is pointing
    fmt.Println("Value stored in y(*p) Before Changing = ", *p)
 
    // changing the value of y by assigning
    // the new value to the pointer
    *p = 500
 
     fmt.Println("Value stored in y(*p) after Changing = ",y)
 
}