Skip to main content

C#7.2 –Readonly struct

C# 7.2 introduces the ability to make struct declaration readonly.

What does this do?

The readonly modifier on a struct definition declares that the struct is immutable. the Every instance field of the struct must be marked readonly, as shown in the following example:

It guarantees that no member of the struct can manipulate its content as it ensures every field is marked as readonly. Adding a field not marked as readonly will generate the following compiler error:

CS8340: "Instance fields of readonly structs must be readonly."

This guarantee is important because it allows the compiler to avoid defensive copies of struct values.  For example when invoking members of a struct which is stored in a readonly field(like the ToString() method in the example above). Invocations like the ToString now occur directly on the field, avoiding the wasteful copy it had to do before.

You can even go one step further by using readonly auto properties. That instructs the compiler to create readonly backing fields for those properties. If we rewrite the code above, it becomes:


Labels:

Popular posts from this blog

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.
Read more

.NET 8–Keyed/Named Services

A feature that a lot of IoC container libraries support but that was missing in the default DI container provided by Microsoft is the support for Keyed or Named Services. This feature allows you to register the same type multiple times using different names, allowing you to resolve a specific instance based on the circumstances. Although there is some controversy if supporting this feature is a good idea or not, it certainly can be handy. To support this feature a new interface IKeyedServiceProvider got introduced in .NET 8 providing 2 new methods on our ServiceProvider instance: object? GetKeyedService(Type serviceType, object? serviceKey); object GetRequiredKeyedService(Type serviceType, object? serviceKey); To use it, we need to register our service using one of the new extension methods: Resolving the service can be done either through the FromKeyedServices attribute: or by injecting the IKeyedServiceProvider interface and calling the GetRequiredKeyedServic...
Read more

Kubernetes–Limit your environmental impact

Reducing the carbon footprint and CO2 emission of our (cloud) workloads, is a responsibility of all of us. If you are running a Kubernetes cluster, have a look at Kube-Green . kube-green is a simple Kubernetes operator that automatically shuts down (some of) your pods when you don't need them. A single pod produces about 11 Kg CO2eq per year( here the calculation). Reason enough to give it a try! Installing kube-green in your cluster The easiest way to install the operator in your cluster is through kubectl. We first need to install a cert-manager: kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.14.5/cert-manager.yaml Remark: Wait a minute before you continue as it can take some time before the cert-manager is up & running inside your cluster. Now we can install the kube-green operator: kubectl apply -f https://github.com/kube-green/kube-green/releases/latest/download/kube-green.yaml Now in the namespace where we want t...
Read more