mirror of
https://github.com/littensy/charm.git
synced 2026-10-21 11:44:08 +00:00
31 lines
989 B
Lua
31 lines
989 B
Lua
local requireReact = require(script.Parent.Parent.modules.React)
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local subscribe = require(script.Parent.Parent.subscribe)
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local types = require(script.Parent.Parent.types)
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type Atom<T> = types.Atom<T>
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type UseAtomState =
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(<State>(atom: Atom<State>) -> State)
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& (<State, Result>(atom: Atom<State>, ((State) -> Result)?) -> State | Result)
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& (<State, Result>(atom: Atom<State>, selector: (State) -> Result) -> Result)
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local function useAtomState<State>(atom: Atom<State>, selector: ((State) -> State)?): State
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local React = requireReact()
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local state, setState = React.useState(function()
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return if selector then selector(atom()) else atom()
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end)
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local latestSelector = React.useRef(selector)
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latestSelector.current = selector
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React.useEffect(function()
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return subscribe(atom, function(state)
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local selector = latestSelector.current
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setState(if selector then selector(state) else state)
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end)
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end, { atom })
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return state
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end
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return useAtomState :: UseAtomState
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