39 lines
1.1 KiB
Lua
39 lines
1.1 KiB
Lua
local Observable = require 'observable'
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local util = require 'util'
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--- Returns a new Observable that produces its most recent value every time the specified observable
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-- produces a value.
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-- @arg {Observable} sampler - The Observable that is used to sample values from this Observable.
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-- @returns {Observable}
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function Observable:sample(sampler)
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if not sampler then error('Expected an Observable') end
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return Observable.create(function(observer)
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local latest = {}
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local function setLatest(...)
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latest = util.pack(...)
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end
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local function onNext()
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return observer:onNext(util.unpack(latest))
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end
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local function onError(message)
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return observer:onError(message)
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end
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local function onCompleted()
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return observer:onCompleted()
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end
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local sourceSubscription = self:subscribe(setLatest, onError)
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local sampleSubscription = sampler:subscribe(onNext, onError, onCompleted)
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return Subscription.create(function()
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if sourceSubscription then sourceSubscription:unsubscribe() end
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if sampleSubscription then sampleSubscription:unsubscribe() end
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end)
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end)
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end
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