mirror of
https://github.com/littensy/charm.git
synced 2026-10-20 17:51:37 +00:00
35 lines
744 B
Lua
35 lines
744 B
Lua
local effect = require(script.Parent.effect)
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local types = require(script.Parent.types)
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type Molecule<T> = types.Molecule<T>
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local function observe<K, V>(molecule: Molecule<{ [K]: V }>, factory: (value: V, key: K) -> () -> ()): () -> ()
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local connections: { [K]: () -> () } = {}
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local unsubscribe = effect(function()
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local state = molecule()
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for key, disconnect in connections do
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if state[key] == nil then
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connections[key] = nil
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disconnect()
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end
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end
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for key, value in state do
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if not connections[key] then
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connections[key] = factory(value, key)
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end
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end
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end)
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local function cleanup()
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unsubscribe()
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for _, disconnect in connections do
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disconnect()
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end
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end
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return cleanup
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end
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return observe
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