I am learning golang development gadgets. There is a scenario in which you need to pass data of map [string] [] string type. Each time, about 5W pieces of data are saved in map and passed to other functions for processing. If you do so, will it consume a lot of memory?. But it seems that map can"t pass a value by passing a pointer? Do you have any good suggestions in this situation? Thank you
I recommend you take a look at an article written by a blogger http://colobu.com/2017/01/05/.
similar to map and slice, references are passed without a copy of the value.
package main
import "fmt"
func main() {
var pointerMap map[string]int = map[string]int{
"a" : 1,
}
pointerB := pointerMap
pointerB["a"] = 2;
fmt.Printf("%v", pointerMap)
}is still the value passed, except that the passed "value" is a 1-word address
[ https://play.golang.org/p/ozH.]
package main
import (
)f "fmt")
func alter_map (a map [int] int) {
a[1] = 2
f.Printf("%p\n", &a) //!!!!!!!!!!!!!1
f.Printf("%p\n", a)//map
}
func main () {
a := make(map[int]int, 2)
a[2] =1
f.Printf("%p\n", &a) //!!!!!!!!!!!!!!
f.Printf("%p\n", a) //map
alter_map(a) //map
f.Println(a)}
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