45 lines
No EOL
673 B
Text
45 lines
No EOL
673 B
Text
import "math/event" for Event
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class Observable{
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value{_value}
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value=(v){
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_event.emit([v])
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_value = v
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}
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value_no_update=(v){_value = v}
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event{_event}
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static new(value){
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var variable = new()
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variable.value_no_update = value
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return variable
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}
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construct new(){
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_event = Event.new()
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}
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on_change(fn){
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return _event.listen(fn)
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}
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on_change(initial, fn){
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if(initial){
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fn.call(value)
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}
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return on_change(fn)
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}
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not_on_change(fn){
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_event.unlisten(fn)
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}
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on_not_null(fn){
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if(value){
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fn.call(value)
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} else {
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_event.once(fn)
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}
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}
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} |