Using if case let to match specific enum case

#swift

When working with enum and need to get associated value from one case, instead of switching and handle all the cases, we can use if case let keyword.

For example if we have enum like this:

import Foundation

enum Message {
	case text(userId: String, date: Date)
	case draft(userId: String, date: Date)
	case join(userId: String, date: Date)
	case leave(userId: String, date: Date)
	case balloon(userId: String, date: Date)
}

then we want to log userId when user send balloon message, we can use if case let

if case let Message.balloon(userId, date) = textMessage {
	log(userId)
}

Linked Notes:

Pattern matching in Enum

While working using [[The Composable Architecture]] I often need to match a specific enum action or dealing with extracting associated value in enum. There’s a few different way to pattern matching an enum and extract its associated value:

Swift in Depth

Author: Tjeerd in ‘t Veen

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