Thursday, October 6, 2022

Golang const map: What are they and why you should use them

A const map is a map data type in the Go programming language that is used to store key-value pairs. The key is used to identify the value, and the value is used to store the data. A const map is immutable, meaning that it cannot be changed. This makes it ideal for storing data that needs to be accessed quickly, such as a cache.

Golang const map: How to make your maps immutable

If you’re working with maps in Golang, you may want to make them immutable (read-only). This can be useful if you want to ensure that your data doesn’t get modified accidentally.

There are two ways to make a map immutable. The first is to use the built-in “make” function:

map := make(map[string]string)

This will create a new map that can’t be modified. If you try to add or remove items from the map, you’ll get an error.

The second way to make a map immutable is to use the “lock” function from the “sync” package:

import "sync"

map := make(map[string]string)
var lock sync.Mutex
defer lock.Unlock()

This will create a lock that will prevent any modifications from being made to the map. You can still access the data in the map, but you can’t modify it.

Golang const map: The benefits of using const maps

There are plenty of benefits to using const maps in Golang. For starters, they’re incredibly efficient. Const maps are stored as a contiguous array, which means they can be accessed faster than other data structures.

Another benefit of using const maps is that they’re immutable. This means that once a const map is created, it cannot be modified. This can be incredibly useful for ensuring data integrity, as well as for avoiding race conditions.

Finally, const maps can be used in conjunction with the built-in range operator to iterate over all key-value pairs. This makes const maps incredibly easy to work with and can greatly simplify your code.