Go-HashMap.go

package main

import (
	"fmt"
	"net/http"
	"os"
)

// HashMap is the implementation of a hash map in Go
type HashMap map[interface{}]interface{}

// Person is a random struct type for demonstration purposes
type Person struct {
	Name  string
	Age   int
	Phone string
}

// Print prints the key-value mappings alone with the data types of a HashMap
func (h *HashMap) Print() {
	for k, v := range *h {
		fmt.Printf(">>> %v (%T) ----> %v (%T)\n\n", k, k, v, v)
	}
}

func main() {
	h := make(HashMap)

	// Mapping String -> *http.Request
	h["HTTP-Request"] = &http.Request{}

	// Mapping os.File -> *os.File
	h[os.File{}], _ = os.Open("blankfile")

	// Mapping struct{} -> int
	h[struct{}{}] = 6

	// Mapping bool -> map[string]string
	h[true] = make(map[string]string)

	// Mapping custom defined Person struct-> custom defined HashMap type
	h[Person{}] = HashMap{}

	h.Print()
}

/*
Output:
>>> HTTP-Request (string) ----> &{ <nil>  0 0 map[] <nil> <nil> 0 [] false  map[] map[] <nil> map[]   <nil> <nil> <nil> <nil>} (*http.Request)

>>> {<nil>} (os.File) ----> &{0xc00005e2a0} (*os.File)

>>> {} (struct {}) ----> 6 (int)

>>> true (bool) ----> map[] (map[string]string)

>>> { 0 } (main.Person) ----> map[] (main.HashMap)

*/