49 lines
1.3 KiB
Fennel
49 lines
1.3 KiB
Fennel
(fn parse-uevent [s]
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(let [at (string.find s "@" 1 true)
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(nl nxt) (string.find s "\0" 1 true)]
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(doto
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(collect [k v (string.gmatch
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(string.sub s (+ 1 nxt))
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"(%g-)=(%g+)")]
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(k:lower) v)
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(tset :path (string.sub s (+ at 1) (- nl 1))))))
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(fn event-matches? [e terms]
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(accumulate [match? true
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name value (pairs terms)]
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(and match? (= value (. e name)))))
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(fn find-in-database [db terms]
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(accumulate [found []
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_ e (pairs db)]
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(if (event-matches? e terms)
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(doto found (table.insert e))
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found)))
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(fn record-event [db subscribers str]
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(let [e (parse-uevent str)]
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(match e.action
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:add (tset db e.path e)
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:change (tset db e.path e)
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;; should we do something for bind?
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:remove (tset db e.path nil)
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)
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(each [_ { : terms : callback } (ipairs subscribers)]
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(if (event-matches? e terms) (callback e)))
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e))
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(fn database []
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(let [db {}
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subscribers []]
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{
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:find (fn [_ terms] (find-in-database db terms))
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:add (fn [_ event-string] (record-event db subscribers event-string))
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:at-path (fn [_ path] (. db path))
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:subscribe (fn [_ callback terms]
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(table.insert subscribers {: callback : terms }))
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}))
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{ : database }
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