Pointer

✅ Pointer and Reference

• *: dereference operator(get/set value at address)
• &: get pointer(get address) operator

• *T: pointer to a value of type T, like str *string

• &before variable: get the reference, address of the variable

• *before variable name: dereference the pointer, go to the pointer and get or set the value of that address

• pointer: variable that stores the memory address of another variable
• y is pointer of int

x := 7
fmt.Println(x)  //print value 7
fmt.Println(&x) //&, get reference, print address 0x14000112020

y := &x //y is pointer
fmt.Println(y) //0x14000112020

*y = 8 //*, dereference the pointer, change value of x
fmt.Println(x) //now x is 8

• *before data type: pointer(get memory address)of that data type

• ☑️ Changes the value of myWord
• if you want to change the value of an immutable, need to pass the pointer

//parameter (str *string)
//*, pass the pointer for this parameter, not the value
//passing the memory address of variable as parameter
//pass memory address of myWord
func changePointer(str *string) {
	*str = "changed1" //*str = change the value of that pointer
}

• ☑️ does NOT change value of myWord

// does not change value of myWord
func changeValue(str string) { //pass value of myWord
str = "changed2"
}

func main(){
	myWord := "hello"
	changePointer(myWord) // <- pass address(0x14000112020)of myWord as param
	changeValue(myWord) // <- pass value "hello" as param
}

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