Understand the advantages and uses of Golang pointers and improve your knowledge

The advantages and uses of Golang pointers, so that you can better understand, you need specific code examples

In the Go language, pointers are a special data type, It stores the memory address of a variable. By using pointers, we can directly operate the memory where the variable is located, and then reference and modify the variable. Compared with other programming languages, Go language pointers have some unique advantages and uses. This article will use specific code examples to let us better understand the advantages and uses of pointers in the Go language.

1. The overhead of passing large objects is smaller

In parameter passing of functions or methods, if a large object is passed directly, it will cause the overhead of copying the entire object, especially is in a recursive call or loop. When passing pointers as parameters, you only need to pass the memory address, avoiding the overhead of object copying. In the following code example, we define a structure type Person, which contains two fields: name and age. We define a function modifyByPointer, using a pointer as a parameter to modify the Person object passed in.

package main

import "fmt"

type Person struct {
    name string
    age  int
}

func modifyByPointer(p *Person) {
    p.name = "Alice"
    p.age = 30
}

func main() {
    p := Person{"Bob", 25}

    modifyByPointer(&p)

    fmt.Println(p)
}

The running result is:

{Alice 30}

As you can see, the modifyByPointer function modifies the passed Person object through a pointer. There is no need to copy the entire object, thus avoiding expensive objects. Copy operation.

2. Dynamic allocation of memory

In Go language, use the keyword new to dynamically allocate a memory space for a type and return the type pointer. In the following code example, we use new to dynamically allocate the memory of an integer variable and assign it to the pointer p.

package main

import "fmt"

func main() {
    p := new(int)
    *p = 10

    fmt.Println(*p)
}

The running result is:

10

As you can see, by using the new keyword, we dynamically allocate memory for the integer variable and use the pointer p to Access and modify the value of this memory space.

3. Function returns multiple results

In Go language, functions can return multiple results. Pointers are very useful when functions return. You can modify the value of external variables through pointers inside the function, thereby achieving multiple return results. In the following code example, we define a function swap to modify the two integer variables passed in through pointers.

package main

import "fmt"

func swap(a *int, b *int) {
    tmp := *a
    *a = *b
    *b = tmp
}

func main() {
    x, y := 10, 20

    swap(&x, &y)

    fmt.Println(x, y)
}

The running result is:

20 10

As you can see, by using pointers inside the function, we successfully exchanged the values ​​of x and y.

To sum up, pointers in the Go language have the advantages and uses of transferring large objects with less overhead, dynamically allocating memory, and functions returning multiple results. By using pointers properly, we can better manage memory and improve program performance and efficiency. I hope the above code examples can help everyone better understand and apply pointers in the Go language.

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