Swift Trick : How to add a computed property to enumeration.

I was found the useful trick in Swift. We create Enumeration for defines a common type for a group of related values. The power of Swift we can add a computed property to enumeration.

We can create simply computed property as shown in the following code :

enum ApiError {
case NoInternetConnection
case AuthenticationFail
case ResponseTimeOut
var errorMsg: String {
switch self {
case .NoInternetConnection:
return “Internet connection has problem!”

case .AuthenticationFail:
return “Error has Authentication fail!”

case .ResponseTimeOut:
return “Too longggggg :P”

Then our enumeration can retrieve errorMsg value as String type.

In code demonstrates how to use them:

let errorFromApi = ApiError.NoInternetConnection
func displayError(error: ApiError) {
// The result will display "Internet connection has problem!"

Nice! Enumerations in Swift are a lot more powerful.
Hopefully, I think you will get some a good trick from Enumerations.
Finally, what’s your opinion about Enumerations?
You can leave your comment below. Let’s share idea!

Thank nice image from

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