golang dictionary code example

Example 1: initialize map in golang

// By default maps in Go behaves like a default dictionary in python
m := make(map[string]int)

m["Dio"] = 3
m["Jonathan"] = 1

Example 2: dictionary in golang

m := make(map[string]float64)

m["pi"] = 3.14             // Add a new key-value pair
m["pi"] = 3.1416           // Update value
fmt.Println(m)             // Print map: "map[pi:3.1416]"

v := m["pi"]               // Get value: v == 3.1416
v = m["pie"]               // Not found: v == 0 (zero value)

_, found := m["pi"]        // found == true
_, found = m["pie"]        // found == false

if x, found := m["pi"]; found {
    fmt.Println(x)
}                           // Prints "3.1416"

delete(m, "pi")             // Delete a key-value pair
fmt.Println(m)              // Print map: "map[]"

Example 3: go add to map

m := make(map[string]int)
m["numberOne"] = 1
m["numberTwo"] = 2

Example 4: dictionary golang

package main

import (
    "fmt"
)

func main() {
    dict := map[interface{}]interface{} {
        1: "hello",
        "hey": 2,
    }
    fmt.Println(dict) // map[1:hello hey:2]
}

Example 5: go get from map

var id string
var ok bool
if x, found := res["strID"]; found {
     if id, ok = x.(string); !ok {
        //do whatever you want to handle errors - this means this wasn't a string
     }
} else {
   //handle error - the map didn't contain this key
}