Go Lang - Maps
Understanding Maps in Go
Maps in Go are unordered collections of key-value pairs.
Key Points:
- Maps are used to store key-value pairs where each key is unique.
- Maps are reference types in Go.
- Elements in a map are accessed using their keys.
Example of Maps in Go
Below is an example demonstrating the use of maps in Go:
// Example: Working with maps in Go
package main
import (
"fmt"
)
func main() {
// Declare and initialize a map
employees := map[string]int{
"John": 35,
"Jane": 29,
"Doe": 40,
}
// Access elements of the map
fmt.Println("Age of John:", employees["John"])
// Add a new key-value pair to the map
employees["Alice"] = 32
// Iterate over the map
fmt.Println("Employees:")
for name, age := range employees {
fmt.Println(name, "-", age)
}
}
Manipulating Maps in Go
Maps in Go support various operations like adding, updating, deleting, and iterating over key-value pairs.
// Example: Manipulating maps in Go
package main
import (
"fmt"
)
func main() {
// Declare and initialize a map
languages := map[string]string{
"en": "English",
"fr": "French",
"es": "Spanish",
}
// Update a value in the map
languages["fr"] = "Français"
// Delete a key from the map
delete(languages, "es")
// Check if a key exists in the map
if lang, ok := languages["en"]; ok {
fmt.Println("Value for 'en':", lang)
} else {
fmt.Println("'en' not found")
}
// Iterate over the map
fmt.Println("Languages:")
for code, name := range languages {
fmt.Println(code, "-", name)
}
}
Summary
This guide provided an overview of understanding and using maps in Go, including examples of declaring maps, accessing map elements, manipulating maps by adding, updating, deleting keys, and iterating over map elements. By using maps effectively, you can manage key-value data pairs efficiently in Go.