OptionaldrawingsOptionalnowOptionalspentWhether a spent alert keeps its line. Defaults to 'show'.
A triggered or expired alert is no longer watching anything, and the two defensible things to do with its line are opposites. Keeping it is this library's default and is why each lifecycle state has its own badge and colour: the line says what became of the level, which is worth knowing on a chart somebody has just come back to.
'hide' is for the host where that reading does not pay. A terminal left
open through a session accumulates levels that will never fire again, and
past a certain number the ones still watching are the hardest to pick out
of them. The alert itself is untouched either way: it stays in list(),
keeps its lifecycle state, still refuses to fire twice, and gets its line
back if a host re-arms it. Only the drawing goes.
OptionalvisualsPriceLine visuals are enabled on chart hosts; disable for a model-only consumer.
Delivery and expiry clock in UTC seconds. Defaults to Date.now() / 1000.