The @Published property wrapper allows any given property to be a publisher and emit its changed values. In the example below the calendarYear property is a publisher and prefixing the property with a $ allows us to subscribe to it or perform publisher operations. As a publisher, combine operators can now be performed on it, here we are using the sink operator to get changed values and print to the console. In an actual app this value can be bind to a UI element using the assign operator.

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