You can use an “update” method to come at least close to assignment syntax:

class Property[T](var value:T) {
def get:T = value
def update(t:T) { value = t }
}

val v = new Property(“hi”)

//this doesn’t work
v = “hello”
–> error: reassignment to val
–> v = “hello”
–> ^

//but this *does* work
v() = “hello”

println(v.get)
–> hello

“The responsibility for data is all back to the watcher, and off the shoulders of the watchable.” In what other language is the responsibility for data on the watchable, not the watcher? What can I compare this to?

Is this example similar to an event-listener pattern?