Golang Study notes: How to choose the receiver type of the method

In the process of writing code, often will be involved in the method of receiver type selection problem, often tangled in the use of T or *t, remember the following principles to solve the problem:

• To modify the instance state, use *t.
• It is recommended to use T for small objects or fixed values without modifying the state.
• Large objects are recommended with *t to reduce replication costs.
• Reference types, strings, dictionaries, functions, and other pointers wrap objects directly with T.
• If synchronization fields such as mutexes are included, use *T to avoid invalid lock operations due to assignment.
• Other uncertain situations are *t.

Methods can be invoked using instance values or pointers, and the compiler will automatically convert between the underlying type and pointer type based on the method receiver type.

type N intfunc (n N)Value(){    n++    fmt.Printf("%p, %v\n",&n,n)}func (n *N)Pointer(){    *n++    fmt.Printf("%p, %v\n",n,*n)}func main() {    var a N = 25    p:=&a    a.Value()    a.Pointer()    p.Value()    p.Pointer()    fmt.Printf("%p, %v\n",&a,a)}

In addition, such as the dictionary itself is the pointer wrapper object, the address is not necessary to add & address characters.