10. Go - Maps

Maps are key-value store. It's an un-ordered list.

Maps are a reference type meaning it will pass a reference of its values instead of a copy.


Creating maps:

var VARIABLE = map[KEY_TYPE]VALUE_TYPE{KEY_VALUE:VALUE_TYPE}

var map1 = map[string]int{}

var variable = make(map[string]int)


Getting value from map:

variable["KEY1"] = 50

variable2["KEY1"] = "KEY2"


Getting value and return whether found:

package main

import "fmt"

func main() {
    var map1 = map[string]int{"TEST": 3}

    v, ok := map1["TEST"]
    fmt.Println(v, ok)

}


Getting value existence and acting upon true:

package main

import "fmt"

func main() {
    var map1 = map[string]int{"TEST": 3}

    if v, ok := map1["TEST"]; ok {
        fmt.Println(v)
        fmt.Println("exists")
    }

}


Deleting key-value from map:

delete(mapvarable,KEY)


Iterating map:

package main

import "fmt"

func main() {
    var map1 = map[string]int{
        "TEST":  3,
        "TEST2": 4,
    }

    for i, e := range map1 {
        fmt.Println(i, "KEY")
        fmt.Println(e, "VALUE")
    }
}



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