Mapped KVal not updated when KVar is set to its initial value

[adamschoenemann]

If you set a KVar back to its initial value, the listening KVals (using map at least) are not updated.
Example code

fun main(args: Array<String>) {
    Kweb(port = 8080) {
        val kv = KVar(0)
        doc.body.new {
            div().new {
                a().on.click { kv.value = 1 }.text("set 1")
            }
            div().new {
                a().on.click { kv.value = 0 }.text("set 0")
            }
            div().new {
                span().text(kv.map { "value: $it" })
            }
        }
    }
}

You can't make the UI update back to "value: 0".

The problem seems to be in KVal:43.