Can Golang functions return values ​​via pointers?

Yes, Go functions can return values ​​through pointers. By returning a pointer value, a function can modify the value of an external variable. The specific steps are as follows: Define a function that returns a pointer type. Within a function, use a pointer to modify the value of an external variable. When calling a function, pass the address of the external variable (i.e. pointer). After calling the function, you can dereference the pointer to obtain the modified value.

# Can a Go function return a value through a pointer?

In the Go language, function return values ​​can be values ​​or reference types (pointers). This article will explore whether Go functions can return values ​​through pointers and provide a practical case.

Pointer return value

In Go, a pointer type is a value type that holds the memory address of other variables. By using pointers, functions can modify the value of external variables.

The function can return a value through a pointer as follows:

func getPtr() *int {
   x := 10
   return &x
}

This function returns a pointer to the variable x. The value of variable x can be obtained by calling this function and dereferencing the pointer:

func main() {
   ptr := getPtr()
   fmt.Println(*ptr) // 输出：10
}

Practical case

Consider a scenario where we have a structure Represents user information, we want to update the user name in the function.

type User struct {
   Name string
   Age int
}

func updateUser(u *User) {
   u.Name = "New Name"
}

func main() {
   user := User{Name: "John", Age: 30}
   updateUser(&user)
   fmt.Println(user.Name) // 输出："New Name"
}

By returning a pointer value, we can modify the value of an external variable inside a function, thereby avoiding creating a copy of the variable.

Notes

Although data sharing between functions can be achieved through pointer return values, you need to pay attention to the following matters:

• Pointers Can be nil, needs to be checked.
• Never return pointers to local variables because these variables will be destroyed after the function exits.
• Must ensure that the pointer points to valid and accessible memory.

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