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refactor: add docs, remove some modules

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littensy 2025-10-03 20:45:01 -07:00
parent 027c5bf8f8
commit 7a63993293
19 changed files with 558 additions and 180 deletions
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17
packages/charm-sync/src/client.luau
View file

@ -6,6 +6,10 @@ type SyncPayload = types.SyncPayload
local atomRegister: { [string]: Charm.Atom } = {}
--- Registers atoms to be kept in sync with the server. Atoms with matching
--- keys on the server will be synced to these atoms.
---
--- @param atoms An object mapping string keys to atoms to be synced.
local function syncAtoms(atoms: { [string]: Charm.Atom })
for key, atom in atoms do
if atomRegister[key] and atomRegister[key] ~= atom then
@ -17,6 +21,11 @@ local function syncAtoms(atoms: { [string]: Charm.Atom })
end
end
--- Unregisters one or more atoms from being kept in sync with the server.
--- The atoms will retain their current values, but will no longer receive
--- updates from the server.
---
--- @param keys The keys of the atoms to stop syncing.
local function unsyncAtoms(...: string)
for index = 1, select("#", ...) do
local key = select(index, ...)
@ -24,6 +33,9 @@ local function unsyncAtoms(...: string)
end
end
--- Unregisters all atoms from being kept in sync with the server. The
--- atoms will retain their current values, but will no longer receive
--- updates from the server.
local function reset()
table.clear(atomRegister)
end
@ -51,6 +63,11 @@ local function applyPatchPayload(data: { [string | number]: any })
end
end
--- Applies one or more payloads received from the server to the synced
--- atoms. Payloads are state patches or initial state updates sent by the
--- server, and are usually received via a remote event.
---
--- @param payloads The payloads to apply.
local function applyPayloads(payloads: { SyncPayload })
for _, payload in payloads do
if payload.type == "init" then

5
packages/charm-sync/src/flatten.luau
View file

@ -2,6 +2,11 @@ type NestedAtomMap = {
[string]: NestedAtomMap | () -> any,
}
--- Flattens a nested atom map into a single object with slash-separated keys.
--- Useful for recursively collecting atoms returned by modules.
---
--- @param atoms The nested atom map to flatten.
--- @return A flattened atom map.
local function flatten(atoms: NestedAtomMap): { [string]: () -> any }
local result: { [string]: () -> any } = {}

128
packages/charm-sync/src/index.d.ts vendored
View file

@ -26,9 +26,6 @@ type DataTypes = {
[P in keyof CheckableTypes as P extends keyof CheckablePrimitives ? never : P]: CheckableTypes[P];
};
/**
* A type that should not be made partial in patches.
*/
type DataType = DataTypes[keyof DataTypes];
/**
@ -63,14 +60,8 @@ export type SyncPayload<Selectors extends SelectorMap = SelectorMap, Serialize e
| { type: "patch"; data: SyncPatch<StateOfMap<Selectors>, Serialize> };
/**
* Checks whether a value is `None`. If `true`, the value is scheduled to be
* removed from the state when the patch is applied.
*
* @param value The value to check.
* @returns `true` if the value is `None`, otherwise `false`.
* Global configuration options that affect the behavior of Charm Sync.
*/
export function isNone(value: unknown): value is None;
export const config: {
/**
* The interval at which to send patches to the client, in seconds.
@ -108,49 +99,142 @@ export const config: {
validatePatches: boolean;
};
/**
* @client
*/
export namespace client {
/**
* Registers atoms to be kept in sync with the server. Atoms with matching
* keys on the server will be synced to these atoms.
*
* @param atoms An object mapping string keys to atoms to be synced.
*/
export function syncAtoms(atoms: { [key: string]: Atom<any> }): void;
/**
* Unregisters one or more atoms from being kept in sync with the server.
* The atoms will retain their current values, but will no longer receive
* updates from the server.
*
* @param keys The keys of the atoms to stop syncing.
*/
export function unsyncAtoms(...keys: string[]): void;
/**
* Unregisters all atoms from being kept in sync with the server. The
* atoms will retain their current values, but will no longer receive
* updates from the server.
*/
export function reset(): void;
/**
* Applies one or more payloads received from the server to the synced
* atoms. Payloads are state patches or initial state updates sent by the
* server, and are usually received via a remote event.
*
* @param payloads The payloads to apply.
*/
export function applyPayloads<Atoms extends { [key: string]: Atom<any> }, Serialize extends boolean = true>(
payloads: SyncPayload<Atoms, Serialize>[],
): void;
}
/**
* @server
*/
export namespace server {
/**
* Registers atoms to be kept in sync with a specific client. Should be
* called when a player joins the game to start syncing atoms to them. Call
* `unsyncAtomsFromClient` or `unsyncClient` to stop syncing.
*
* Each atom should be assigned a unique key, allowing the server to re-use
* patches between multiple clients.
*
* @param client The player to sync atoms to.
* @param atoms An object mapping string keys to atoms to be synced.
*/
export function syncAtomsToClient(client: Player, atoms: { [key: string]: Atom<any> }): void;
/**
* Unregisters one or more atoms from being kept in sync with a specific
* client.
*
* @param client The player to stop syncing atoms to.
* @param keys The keys of the atoms to stop syncing.
*/
export function unsyncAtomsFromClient(client: Player, ...keys: string[]): void;
/**
* Unregisters all atoms from being kept in sync with a specific client.
* Should be called when a player leaves the game.
*
* @param client The player to stop syncing atoms to.
*/
export function unsyncClient(client: Player): void;
/**
* Starts automatically syncing registered atoms to clients. Patches will
* be sent to clients whenever the atoms are updated.
*
* @param onSync The function to call when patches can be sent to a client.
* @returns `stopSync()`
*/
export function startSync<Atoms extends { [key: string]: Atom<any> }, Serialize extends boolean = true>(
onSync: (client: Player, payloads: SyncPayload<Atoms, Serialize>[]) => void,
): Cleanup;
/**
* Stops automatically syncing registered atoms to clients. Patches will
* no longer be sent to clients until `startSync` is called again.
*/
export function stopSync(): void;
/**
* Immediately sends pending updates and initial states to all clients.
* Normally, updates are sent at the interval specified in `config.interval`.
* Calling this function forces all pending updates to be sent immediately.
*/
export function flush(): void;
/**
* Unregisters all atoms from being kept in sync with all clients, and
* stops automatic syncing.
*/
export function reset(): void;
}
export namespace patch {
export function isNone(value: unknown): value is None;
/**
* Converts `nil` values to the special `None` symbol. This is useful when
* preparing data for serialization, since `nil` can represent both the absence
* of a value and the removal of a value in patches.
*/
export function nilToNone<T>(value: T | undefined): T | None;
/**
* Compares two states and returns a patch that can be applied to the
* current state to produce the next state.
*
* @param currentState The current state.
* @param nextState The next state.
* @returns A patch that can be applied to the current state.
*/
export function diff<State, Serialize extends boolean = true>(
currentState: State,
nextState: State,
): SyncPatch<State, Serialize>;
/**
* Applies a patch to a state and returns the resulting value.
*
* @param currentState The current state.
* @param statePatch The patches to apply.
* @returns The new state with the patch applied.
*/
export function apply<State, Serialize extends boolean = true>(
state: State,
patch: SyncPatch<State, Serialize>,
currentState: State,
statePatch: SyncPatch<State, Serialize>,
): State;
}
@ -170,7 +254,10 @@ type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (
type IntersectValues<T> = UnionToIntersection<{ readonly [K in keyof T]: T[K] }[keyof T]>;
type FlattenNestedAtoms<Atoms extends NestedAtomMap, Path extends Key | undefined = undefined> = IntersectValues<{
export type FlattenNestedAtoms<
Atoms extends NestedAtomMap,
Path extends Key | undefined = undefined,
> = IntersectValues<{
readonly [Name in keyof Atoms as AppendPath<Path, Name>]: Atoms[Name] extends Atom<any>
? { readonly [K in AppendPath<Path, Name>]: Atoms[Name] }
: Atoms[Name] extends NestedAtomMap
@ -183,6 +270,15 @@ type FlattenNestedAtoms<Atoms extends NestedAtomMap, Path extends Key | undefine
* Useful for recursively collecting atoms returned by modules.
*
* @param atoms The nested atom map to flatten.
* @return A flattened atom map.
* @returns A flattened atom map.
*/
export function flatten<Atoms extends NestedAtomMap>(atoms: Atoms): FlattenNestedAtoms<Atoms>;
/**
* Checks whether a value is `None`. If `true`, the value is scheduled to be
* removed from the state when the patch is applied.
*
* @param value The value to check.
* @returns `true` if the value is `None`, otherwise `false`.
*/
export function isNone(value: unknown): value is None;

36
packages/charm-sync/src/patch.luau
View file

@ -11,7 +11,11 @@ export type None = types.None
--- deleted values in patches.
local None: None = { __none = "__none" }
--- Checks if a value is the special `None` symbol.
--- Checks whether a value is `None`. If `true`, the value is scheduled to be
--- removed from the state when the patch is applied.
---
--- @param value The value to check.
--- @return `true` if the value is `None`, otherwise `false`.
local function isNone(value: any): boolean
return type(value) == "table" and value.__none == "__none"
end
@ -48,30 +52,30 @@ local function stringifySparseArray(object: { any }): { [string | number]: any }
return dictionary
end
--- Compares two states and returns a patch that can be applied to the previous
--- Compares two states and returns a patch that can be applied to the current
--- state to produce the next state.
---
--- @param prevState The previous state.
--- @param currentState The current state.
--- @param nextState The next state.
--- @returns A patch that can be applied to the previous state.
local function diff(prevState: any, nextState: any): any
if prevState == nextState then
--- @return A patch that can be applied to the current state.
local function diff(currentState: any, nextState: any): any
if currentState == nextState then
return nil
elseif nextState == nil then
return None
elseif type(prevState) ~= "table" or type(nextState) ~= "table" then
elseif type(currentState) ~= "table" or type(nextState) ~= "table" then
return nextState
end
local patches: { [any]: any } = table.clone(nextState)
for key, previous in prevState do
for key, previous in currentState do
patches[key] = diff(previous, nextState[key])
end
if config.autoSerialize then
-- Coerce sparse array patches into dictionaries
if prevState[1] ~= nil or nextState[1] ~= nil then
if currentState[1] ~= nil or nextState[1] ~= nil then
patches = stringifySparseArray(patches)
end
@ -85,20 +89,20 @@ local function diff(prevState: any, nextState: any): any
return patches
end
--- Applies a patch to a state and returns the next state.
--- Applies a patch to a state and returns the resulting value.
---
--- @param prevState The current state.
--- @param currentState The current state.
--- @param statePatch The patches to apply.
--- @returns The next state.
local function apply(prevState: any, statePatch: any): any
--- @return The new state with the patch applied.
local function apply(currentState: any, statePatch: any): any
if isNone(statePatch) then
return nil
elseif type(prevState) ~= "table" or type(statePatch) ~= "table" then
elseif type(currentState) ~= "table" or type(statePatch) ~= "table" then
return statePatch
end
local nextState = table.clone(prevState)
local stateIsArray = prevState[1] ~= nil
local nextState = table.clone(currentState)
local stateIsArray = currentState[1] ~= nil
for key, value in statePatch do
-- Diff-checking an array produces a sparse array, which will not be

40
packages/charm-sync/src/server.luau
View file

@ -20,7 +20,9 @@ local LISTENING_FOR_CHANGES: SyncStatus = 1
local atomRegister: { [string]: RegisteredAtom } = {}
local clientRegister: { [any]: { [string]: SyncStatus } } = {}
local globalUpdates: { { key: string, value: any, previousValue: any } } = {}
local connection: RBXScriptConnection?
local onSyncCallback: (client: any, payloads: { SyncPayload }) -> ()?
local function registerAtom<T>(key: string, atom: () -> T)
if atomRegister[key] then
@ -196,6 +198,15 @@ local function createPayloadsForClient(client: any, patchData: any): { SyncPaylo
return payloads
end
--- Registers atoms to be kept in sync with a specific client. Should be
--- called when a player joins the game to start syncing atoms to them. Call
--- `unsyncAtomsFromClient` or `unsyncClient` to stop syncing.
---
--- Each atom should be assigned a unique key, allowing the server to re-use
--- patches between multiple clients.
---
--- @param client The player to sync atoms to.
--- @param atoms An object mapping string keys to atoms to be synced.
local function syncAtomsToClient(client: any, atoms: { [string]: () -> any })
if not clientRegister[client] then
clientRegister[client] = {}
@ -214,10 +225,19 @@ local function syncAtomsToClient(client: any, atoms: { [string]: () -> any })
end
end
--- Unregisters all atoms from being kept in sync with a specific client.
--- Should be called when a player leaves the game.
---
--- @param client The player to stop syncing atoms to.
local function unsyncClient(client: any)
clientRegister[client] = nil
end
--- Unregisters one or more atoms from being kept in sync with a specific
--- client.
---
--- @param client The player to stop syncing atoms to.
--- @param keys The keys of the atoms to stop syncing.
local function unsyncAtomsFromClient(client: any, ...: string)
local syncedAtoms = clientRegister[client]
@ -235,11 +255,14 @@ local function unsyncAtomsFromClient(client: any, ...: string)
end
end
local function onSyncCallback(_client: any, _payloads: { SyncPayload })
warn("[Charm] Override the onSync function by passing a custom function to startSync")
end
--- Immediately sends pending updates and initial states to all clients.
--- Normally, updates are sent at the interval specified in `config.interval`.
--- Calling this function forces all pending updates to be sent immediately.
local function flush()
if not onSyncCallback then
return
end
local patches = if config.preserveHistory then createHistoricalPatches() else createPatch()
-- While payload objects are technically mutable as they are unique to
@ -266,6 +289,8 @@ local function flush()
table.clear(globalUpdates)
end
--- Stops automatically syncing registered atoms to clients. Patches will
--- no longer be sent to clients until `startSync` is called again.
local function stopSync()
if connection then
connection:Disconnect()
@ -273,6 +298,8 @@ local function stopSync()
end
end
--- Unregisters all atoms from being kept in sync with all clients, and
--- stops automatic syncing.
local function reset()
table.clear(atomRegister)
table.clear(clientRegister)
@ -280,6 +307,11 @@ local function reset()
stopSync()
end
--- Starts automatically syncing registered atoms to clients. Patches will
--- be sent to clients whenever the atoms are updated.
---
--- @param onSync The function to call when patches can be sent to a client.
--- @return `stopSync()`
local function startSync(onSync: (client: any, payloads: { SyncPayload }) -> ()): () -> ()
if connection then
connection:Disconnect()

2
packages/charm-sync/src/types.luau
View file

@ -14,4 +14,4 @@ export type SyncPayload =
--- differentiate between a value that was set to `nil` and an unchanged value.
export type None = { __none: "__none" }
return nil
return {}

9
packages/charm/src/__tests__/core/computed.spec.luau
View file

@ -81,13 +81,12 @@ test("should not update if the atom value is reverted", function()
assert(times == 1, "computed ran when it should not")
end)
test("should accept equality function", function()
test("should receive previous value", function()
local calls = {}
local src = atom(0)
local c1 = computed(function()
return src()
end, function(current, incoming)
return current == incoming or incoming % 2 == 1
local c1 = computed(function(current): number
local incoming = src()
return if current == incoming or incoming % 2 == 1 then current or incoming else incoming
end)
effect(function()

0
packages/charm/src/system.luau → packages/charm/src/alien.luau
View file

23
packages/charm/src/batched.luau
View file

@ -1,23 +0,0 @@
local core = require("./core")
local flags = require("./flags")
local utils = require("./utils")
local startBatch = core.startBatch
local endBatch = core.endBatch
local noYield = utils.noYield
local function handleBatched(ok: boolean, ...)
endBatch()
if ok then
return ...
else
error((...))
end
end
local function batched<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
startBatch()
return handleBatched((if flags.strict then noYield else pcall)(callback, ...))
end
return batched

165
packages/charm/src/core.luau
View file

@ -2,16 +2,16 @@
-- https://github.com/stackblitz/alien-signals
-- https://github.com/Nicell/alien-signals-luau
local alien = require("./alien")
local config = require("./flags")
local system = require("./system")
local utils = require("./utils")
export type ReactiveFlags = system.ReactiveFlags
export type ReactiveNode = system.ReactiveNode
export type Link = system.Link
export type ReactiveFlags = alien.ReactiveFlags
export type ReactiveNode = alien.ReactiveNode
export type Link = alien.Link
local ReactiveFlags = system.ReactiveFlags
local createReactiveSystem = system.createReactiveSystem
local ReactiveFlags = alien.ReactiveFlags
local createReactiveSystem = alien.createReactiveSystem
local deepFreeze = utils.deepFreeze
local noYield = utils.noYield
@ -23,11 +23,11 @@ local PENDING = 0b0100000
local QUEUED = 0b1000000
local UNTRACKED = 0b10000000
export type EffectScope = ReactiveNode & {
type EffectScope = ReactiveNode & {
cleanups: { () -> () },
}
export type Effect = ReactiveNode & {
type Effect = ReactiveNode & {
fn: (dispose: () -> ()) -> ...(() -> ())?,
cleanups: { () -> () },
cleanup: () -> (),
@ -36,7 +36,6 @@ export type Effect = ReactiveNode & {
type Computed<T = any> = ReactiveNode & {
value: T?,
getter: (previousValue: T?) -> T,
equals: ((T, T) -> boolean)?,
}
type Atom<T = any> = ReactiveNode & {
@ -94,16 +93,6 @@ local function runCleanups(effect: EffectScope)
table.clear(effect.cleanups)
end
local function onCleanup(cleanup: () -> (), failSilently: boolean?)
if activeSub and (activeSub :: Effect).cleanups then
table.insert((activeSub :: Effect).cleanups, cleanup)
elseif activeScope then
table.insert(activeScope.cleanups, cleanup)
elseif not failSilently then
warn(debug.traceback("onCleanup() can only be called inside an effect or a scope.", 2))
end
end
local function run(effect: Effect, flags: ReactiveFlags): ()
if bit32.btest(flags, DIRTY) or (bit32.btest(flags, PENDING) and checkDirty(effect.deps :: Link, effect)) then
runCleanups(effect)
@ -171,8 +160,7 @@ local function updateComputed(computed: Computed): boolean
if not success then
error(result)
end
local equals = computed.equals
if if equals then not equals(oldValue, result) else oldValue ~= result then
if oldValue ~= result then
computed.value = result
return true
else
@ -321,26 +309,63 @@ local function unwatched(node: ReactiveNode)
end
end
local function atom<T>(initialValue: T, equals: ((T, T) -> boolean)?): (...((T) -> T) | T) -> T
--- Creates a reactive atom that acts as both a getter and setter. Calling the
--- atom with an argument sets its value, while calling it with no arguments
--- returns its current value.
---
--- @param value The initial value of the atom. If empty, the atom's value will be `undefined`.
--- @param equals A comparator function to determine if the atom's value has changed.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#atomstate-options
local function atom<T>(value: T, equals: ((T, T) -> boolean)?): (...((T) -> T) | T) -> T
if config.frozen then
deepFreeze(initialValue)
deepFreeze(value)
end
return atomGetterSetter({
previousValue = initialValue,
value = initialValue,
previousValue = value,
value = value,
flags = MUTABLE,
equals = equals,
})
end
local function computed<T>(getter: (previousValue: T?) -> T, equals: ((T, T) -> boolean)?): () -> T
--- Creates a new atom that is computed based on the values of other atoms.
--- The returned atom is read-only, and its value is automatically updated when
--- any atoms accessed from within the getter function change.
---
--- If an initial value is provided, the getter will receive this value as its
--- first argument on the initial run, instead of `undefined`.
---
--- @example
--- ```ts
--- const count = atom(1);
--- const plusOne = computed(() => count() + 1);
--- print(plusOne()); // 2
--- ```
---
--- @param getter A function that produces the next value.
--- @param value An optional initial value for the selector.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#computedcallback-options
local function computed<T>(getter: (previousValue: T?) -> T, value: T?): () -> T
return computedGetter({
flags = bit32.bor(MUTABLE, DIRTY),
getter = getter,
equals = equals,
value = value,
})
end
--- Creates an effect that runs a callback in response to atom state changes.
--- An effect tracks which atoms are accessed during its execution, and re-runs
--- the callback when those atoms change.
---
--- The effect callback may return a cleanup function, which gets called once,
--- either before the effect re-runs or when it is disposed.
---
--- If the effect is called within another effect, it will be disposed when the
--- outer effect re-runs.
---
--- @param fn The function to run when dependencies change.
--- @return A function for disposing the effect.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#effectcallback
local function effect(fn: (dispose: () -> ()) -> ...(() -> ())?): () -> ()
local self: Effect = {
fn = fn,
@ -365,6 +390,14 @@ local function effect(fn: (dispose: () -> ()) -> ...(() -> ())?): () -> ()
return self.cleanup
end
--- Creates an effect scope that can capture multiple reactive effects (i.e.
--- computed, effect, subscribe) created within it so that they can be disposed
--- together.
---
--- @param fn A function that may create reactive effects.
--- @param detached If true, the scope will not be automatically disposed of when the parent scope is disposed. Defaults to false.
--- @return A function for disposing all effects created within the scope.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#effectscopecallback-detached
local function effectScope(fn: () -> ...(() -> ())?, detached: boolean?): () -> ()
local self: EffectScope = {
flags = NONE,
@ -386,6 +419,81 @@ local function effectScope(fn: () -> ...(() -> ())?, detached: boolean?): () ->
return effectStop(self)
end
--- Registers a cleanup function to the current active effect or effect scope.
--- If there is no active effect or scope, a warning is logged and the callback
--- is not registered, unless `failSilently` is set to true.
---
--- @param callback The cleanup function to register.
--- @param failSilently If true, suppresses the warning when there is no active effect or scope. Defaults to false.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#oncleanupcallback-failsilently
local function onCleanup(cleanup: () -> (), failSilently: boolean?)
if activeSub and (activeSub :: Effect).cleanups then
table.insert((activeSub :: Effect).cleanups, cleanup)
elseif activeScope then
table.insert(activeScope.cleanups, cleanup)
elseif not failSilently then
warn(debug.traceback("onCleanup() can only be called inside an effect or a scope.", 2))
end
end
--- Runs the callback without subscribing to atom updates or capturing inner
--- effects in the parent effect or scope.
---
--- For an alternative that still cleans up inner effects, use `peek` instead.
---
--- @param callback The callback function.
--- @param args Arguments to pass to the callback.
--- @return The return value of the callback.
local function untracked<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
local prevSub = setCurrentSub(nil)
local prevScope = setCurrentScope(nil)
local results: { any } = { pcall(callback, ...) }
setCurrentSub(prevSub)
setCurrentScope(prevScope)
if not results[1] then
error(results[2])
end
return unpack(results, 2)
end
--- Runs the callback without subscribing to atom updates, but still captures
--- inner effects so that they dispose with the parent effect.
---
--- To avoid capturing inner effects, use `untracked` instead.
---
--- @param callback The callback function.
--- @param args Arguments to pass to the callback.
--- @return The return value of the callback.
local function peek<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
if not activeSub or bit32.btest(activeSub.flags, UNTRACKED) then
return callback(...)
else
activeSub.flags = bit32.bor(activeSub.flags, UNTRACKED)
local results: { any } = { pcall(callback, ...) }
activeSub.flags = bit32.band(activeSub.flags, bit32.bnot(UNTRACKED))
if not results[1] then
error(results[2])
end
return unpack(results, 2)
end
end
--- Combines multiple atom updates into a single "commit" that runs effects at
--- the end of the provided callback.
---
--- @param callback A function that performs multiple atom updates.
--- @param args Arguments to pass to the callback.
--- @return The return value of the callback.
local function batched<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
startBatch()
local results: { any } = { (if config.strict then noYield else pcall)(callback, ...) }
endBatch()
if not results[1] then
error(results[2])
end
return unpack(results, 2)
end
local reactiveSystem = createReactiveSystem({
update = update,
notify = notify,
@ -415,4 +523,7 @@ return {
computed = computed,
effect = effect,
effectScope = effectScope,
untracked = untracked,
peek = peek,
batched = batched,
}

172
packages/charm/src/index.d.ts vendored
View file

@ -1,6 +1,11 @@
type Key = string | number | symbol;
type Cleanup = () => void;
/**
* A reactive atom that acts as both a getter and setter. Calling the atom with
* an argument sets its value, while calling it with no arguments returns its
* current value.
*/
export interface Atom<T> {
(value: T | ((value: T) => T)): T;
(): T;
@ -10,29 +15,130 @@ export type Selector<T> = () => T;
export type Equals<T> = (current: T, incoming: T) => boolean;
/**
* Global flags that modify the behavior of Charm's reactive system.
*/
export const flags: {
/**
* Enforces synchronous, non-yielding behavior in atoms and effects.
* Also enables state validation in Charm Sync to catch sync errors early.
* Enabled if the optimization level is below 2, which is true in studio.
*/
strict: boolean;
/**
* Enforces immutability of atoms by deep-freezing table values. Enabled
* if the optimization level is below 2, which is true in studio.
*/
frozen: boolean;
/**
* Whether inner effects should clean up after themselves when their
* parent effect re-runs. This is usually desirable, but can be disabled
* to revert to the old behavior. Defaults to `true`.
*/
trackInnerEffects: boolean;
};
/**
* Creates a reactive atom that acts as both a getter and setter. Calling the
* atom with an argument sets its value, while calling it with no arguments
* returns its current value.
*
* @param value The initial value of the atom. If empty, the atom's value will be `undefined`.
* @param equals A comparator function to determine if the atom's value has changed.
* @see https://github.com/littensy/charm?tab=readme-ov-file#atomstate-options
*/
export function atom<T>(value: T, equals?: Equals<T>): Atom<T>;
// Overload for undefined initial value
export function atom<T>(): Atom<T | undefined>;
export function computed<T>(getter: (previousValue?: T) => T, equals?: Equals<T>): () => T;
/**
* Creates a new atom that is computed based on the values of other atoms.
* The returned atom is read-only, and its value is automatically updated when
* any atoms accessed from within the getter function change.
*
* If an initial value is provided, the getter will receive this value as its
* first argument on the initial run, instead of `undefined`.
*
* @example
* ```ts
* const count = atom(1);
* const plusOne = computed(() => count() + 1);
* print(plusOne()); // 2
* ```
*
* @param getter A function that produces the next value.
* @param value An optional initial value for the selector.
* @see https://github.com/littensy/charm?tab=readme-ov-file#computedcallback-options
*/
export function computed<T>(getter: (previousValue?: T) => T): () => T;
export function computed<T>(getter: (previousValue: T) => T, value: T): () => T;
/**
* Creates an effect that runs a callback in response to atom state changes.
* An effect tracks which atoms are accessed during its execution, and re-runs
* the callback when those atoms change.
*
* The effect callback may return a cleanup function, which gets called once,
* either before the effect re-runs or when it is disposed.
*
* If the effect is called within another effect, it will be disposed when the
* outer effect re-runs.
*
* @param callback The function to run when dependencies change.
* @returns A function for disposing the effect.
* @see https://github.com/littensy/charm?tab=readme-ov-file#effectcallback
*/
export function effect(callback: (dispose: Cleanup) => Cleanup | void): Cleanup;
/**
* Creates an effect scope that can capture multiple reactive effects (i.e.
* computed, effect, subscribe) created within it so that they can be disposed
* together.
*
* @param callback A function that may create reactive effects.
* @param detached If true, the scope will not be automatically disposed of
* when the parent scope is disposed. Defaults to false.
* @returns A function for disposing all effects created within the scope.
* @see https://github.com/littensy/charm?tab=readme-ov-file#effectscopecallback-detached
*/
export function effectScope(callback: () => Cleanup | void, detached?: boolean): Cleanup;
/**
* Creates an effect that only runs the callback when the value returned by the
* getter changes. The callback receives the new value and the previous value
* as arguments.
*
* @param getter A function that returns the value to watch.
* @param callback The function to run when the value changes.
* @returns A function for disposing the effect.
* @see https://github.com/littensy/charm?tab=readme-ov-file#subscribegetter-callback
*/
export function subscribe<T>(getter: () => T, callback: (value: T, previousValue: T) => void): Cleanup;
/**
* Creates an effect that runs the callback one immediately, and then again
* when the value returned by the getter changes. The callback receives the new
* value, the previous value, and a cleanup function as arguments.
*
* @param getter A function that returns the value to watch.
* @param callback The function to run when the value changes.
* @returns A function for disposing the effect.
* @see https://github.com/littensy/charm?tab=readme-ov-file#listengetter-callback
*/
export function listen<T>(
getter: () => T,
listener: (value: T, previousValue: T | undefined, dispose: Cleanup) => void,
callback: (value: T, previousValue: T | undefined, dispose: Cleanup) => void,
): Cleanup;
export function subscribe<T>(getter: () => T, listener: (value: T, previousValue: T) => void): Cleanup;
/**
* Creates a new atom that is computed by mapping over the entries of an
* existing atom. The returned atom is read-only, and its value is
* automatically updated when the source atom changes.
*
* @param getter A function that returns the table to map over.
* @param mapper A function that transforms each value-key pair from the source
* into a new value or value-key pair for the resulting table.
* @see https://github.com/littensy/charm?tab=readme-ov-file#mappedgetter-mapper
*/
export function mapped<VI, KI, VO, KO = KI>(
getter: () => Map<KI, VI> | ReadonlyMap<KI, VI>,
mapper: (value: VI, key: KI) => LuaTuple<[VO, KO]> | VO,
@ -48,6 +154,19 @@ export function mapped<VI, KI extends Key, VO, KO extends Key = KI>(
mapper: (value: VI, key: KI) => LuaTuple<[VO, KO]> | VO,
): () => { readonly [K in KO]: VO };
/**
* Calls the observer function for each unique key in the table returned by the
* getter. The observer is called once for each key, and again when a new key
* is added.
*
* The observer may return a cleanup function, which will be called when the
* key is removed or when the entire observer is disposed.
*
* @param getter A function that returns the table to observe.
* @param observer A function that is called for each key in the table.
* @returns A function for disposing the observer.
* @see https://github.com/littensy/charm?tab=readme-ov-file#observegetter-observer
*/
export function observe<V, K = number>(
getter: () => Map<K, V> | ReadonlyMap<K, V> | readonly V[],
observer: (value: V, key: K) => Cleanup | void,
@ -58,13 +177,48 @@ export function observe<V, K extends Key>(
observer: (value: V, key: K) => Cleanup | void,
): Cleanup;
export function batched<Args extends any[], Result>(
callback: (...args: Args) => Result,
...args: Args
): (...args: Args) => Result;
/**
* Combines multiple atom updates into a single "commit" that runs effects at
* the end of the provided callback.
*
* @param callback A function that performs multiple atom updates.
* @param args Arguments to pass to the callback.
* @returns The return value of the callback.
*/
export function batched<Args extends any[], Result>(callback: (...args: Args) => Result, ...args: Args): Result;
/**
* Runs the callback without subscribing to atom updates or capturing inner
* effects in the parent effect or scope.
*
* For an alternative that still cleans up inner effects, use `peek` instead.
*
* @param callback The callback function.
* @param args Arguments to pass to the callback.
* @returns The return value of the callback.
*/
export function untracked<Args extends any[], Result>(callback: (...args: Args) => Result, ...args: Args): Result;
/**
* Runs the callback without subscribing to atom updates, but still captures
* inner effects so that they dispose with the parent effect.
*
* To avoid capturing inner effects, use `untracked` instead.
*
* @param callback The callback function.
* @param args Arguments to pass to the callback.
* @returns The return value of the callback.
*/
export function peek<Args extends any[], Result>(callback: (...args: Args) => Result, ...args: Args): Result;
/**
* Registers a cleanup function to the current active effect or effect scope.
* If there is no active effect or scope, a warning is logged and the callback
* is not registered, unless `failSilently` is set to true.
*
* @param callback The cleanup function to register.
* @param failSilently If true, suppresses the warning when there is no active
* effect or scope. Defaults to false.
* @see https://github.com/littensy/charm?tab=readme-ov-file#oncleanupcallback-failsilently
*/
export function onCleanup(callback: Cleanup, failSilently?: boolean): void;

13
packages/charm/src/init.luau
View file

@ -1,32 +1,33 @@
local batched = require("@self/batched")
local core = require("@self/core")
local flags = require("@self/flags")
local listen = require("@self/listen")
local mapped = require("@self/mapped")
local observe = require("@self/observe")
local peek = require("@self/peek")
local subscribe = require("@self/subscribe")
local types = require("@self/types")
local untracked = require("@self/untracked")
local utils = require("@self/utils")
--- A reactive atom that acts as both a getter and setter. Calling the atom with
--- an argument sets its value, while calling it with no arguments returns its
--- current value.
export type Atom<T = any> = types.Atom<T>
export type Selector<T = any> = types.Selector<T>
return {
core = core,
flags = flags,
atom = core.atom,
batched = core.batched,
computed = core.computed,
effect = core.effect,
effectScope = core.effectScope,
onCleanup = core.onCleanup,
batched = batched,
peek = core.peek,
untracked = core.untracked,
listen = listen,
mapped = mapped,
observe = observe,
peek = peek,
subscribe = subscribe,
untracked = untracked,
deepFreeze = utils.deepFreeze,
}

14
packages/charm/src/listen.luau
View file

@ -1,10 +1,18 @@
local core = require("./core")
local peek = require("./peek")
local computed = core.computed
local effect = core.effect
local peek = core.peek
local function listen<T>(getter: () -> T, listener: (state: T, previous: T?, dispose: () -> ()) -> ()): () -> ()
--- Creates an effect that runs the callback one immediately, and then again
--- when the value returned by the getter changes. The callback receives the new
--- value, the previous value, and a cleanup function as arguments.
---
--- @param getter A function that returns the value to watch.
--- @param callback The function to run when the value changes.
--- @return A function for disposing the effect.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#listengetter-callback
local function listen<T>(getter: () -> T, callback: (state: T, previous: T?, dispose: () -> ()) -> ()): () -> ()
local tracked = computed(function()
return getter()
end)
@ -19,7 +27,7 @@ local function listen<T>(getter: () -> T, listener: (state: T, previous: T?, dis
dispose = effect(function()
local previous = current
current = tracked()
peek(listener, current, previous, dispose)
peek(callback, current, previous, dispose)
end)
if disposed then

19
packages/charm/src/mapped.luau
View file

@ -36,7 +36,9 @@ local function mapped<KI, VI, KO, VO>(getter: () -> { [KI]: VI }, mapper: (item:
local cachedKey = keyCache[key]
if cachedKey then
currentOutput = if currentOutput == previousOutput then table.clone(currentOutput) else currentOutput
if currentOutput == previousOutput then
currentOutput = table.clone(currentOutput)
end
currentOutput[cachedKey] = nil
keyCache[key] = nil
end
@ -50,7 +52,9 @@ local function mapped<KI, VI, KO, VO>(getter: () -> { [KI]: VI }, mapper: (item:
local valueOut, keyOut = map(value, key)
if currentOutput[keyOut] ~= valueOut then
currentOutput = if currentOutput == previousOutput then table.clone(currentOutput) else currentOutput
if currentOutput == previousOutput then
currentOutput = table.clone(currentOutput)
end
currentOutput[keyOut] = valueOut
keyCache[key] = keyOut
end
@ -60,4 +64,13 @@ local function mapped<KI, VI, KO, VO>(getter: () -> { [KI]: VI }, mapper: (item:
end)
end
return mapped :: Mapped
--- Creates a new atom that is computed by mapping over the entries of an
--- existing atom. The returned atom is read-only, and its value is
--- automatically updated when the source atom changes.
---
--- @param getter A function that returns the table to map over.
--- @param mapper A function that transforms each value-key pair from the source into a new value or value-key pair for the resulting table.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#mappedgetter-mapper
local mapped = mapped :: Mapped
return mapped

16
packages/charm/src/observe.luau
View file

@ -1,4 +1,5 @@
local core = require("./core")
local flags = require("./flags")
local effect = core.effect
local effectScope = core.effectScope
@ -6,6 +7,17 @@ local onCleanup = core.onCleanup
local startBatch = core.startBatch
local endBatch = core.endBatch
--- Calls the observer function for each unique key in the table returned by the
--- getter. The observer is called once for each key, and again when a new key
--- is added.
---
--- The observer may return a cleanup function, which will be called when the
--- key is removed or when the entire observer is disposed.
---
--- @param getter A function that returns the table to observe.
--- @param observer A function that is called for each key in the table.
--- @return A function for disposing the observer.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#observegetter-observer
local function observe<K, V>(getter: () -> { [K]: V }, observer: (item: V, key: K) -> ...(() -> ())?): () -> ()
local scopes: { [K]: () -> () } = {}
local currentItems: { [K]: V } = {}
@ -45,7 +57,9 @@ local function observe<K, V>(getter: () -> { [K]: V }, observer: (item: V, key:
end
end)
onCleanup(disposeScopes, true)
if flags.trackInnerEffects then
onCleanup(disposeScopes, true)
end
return function()
disposeEffect()

27
packages/charm/src/peek.luau
View file

@ -1,27 +0,0 @@
local core = require("./core")
local UNTRACKED = core.ReactiveFlags.Untracked
local getCurrentSub = core.getCurrentSub
local function handlePeek(sub: core.ReactiveNode?, ok: boolean, ...)
if sub then
sub.flags = bit32.band(sub.flags, bit32.bnot(UNTRACKED))
end
if ok then
return ...
else
error((...))
end
end
local function peek<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
local sub = getCurrentSub()
if not sub or bit32.btest(sub.flags, UNTRACKED) then
return callback(...)
else
sub.flags = bit32.bor(sub.flags, UNTRACKED)
end
return handlePeek(sub, pcall(callback, ...))
end
return peek

14
packages/charm/src/subscribe.luau
View file

@ -1,10 +1,18 @@
local core = require("./core")
local peek = require("./peek")
local computed = core.computed
local effect = core.effect
local peek = core.peek
local function subscribe<T>(getter: () -> T, listener: (state: T, lastState: T) -> ()): () -> ()
--- Creates an effect that only runs the callback when the value returned by the
--- getter changes. The callback receives the new value and the previous value
--- as arguments.
---
--- @param getter A function that returns the value to watch.
--- @param callback The function to run when the value changes.
--- @return A function for disposing the effect.
--- @see https://github.com/littensy/charm?tab=readme-ov-file#subscribegetter-callback
local function subscribe<T>(getter: () -> T, callback: (state: T, lastState: T) -> ()): () -> ()
local tracked = computed(function()
return getter()
end)
@ -18,7 +26,7 @@ local function subscribe<T>(getter: () -> T, listener: (state: T, lastState: T)
if mounted then
mounted = false
else
peek(listener, current, previous)
peek(callback, current, previous)
end
end)
end

2
packages/charm/src/types.luau
View file

@ -1,5 +1,7 @@
type Update<T> = ((previous: T) -> T) | T
export type Atom<T> = (...Update<T>) -> T
export type Selector<T> = () -> T
return {}

36
packages/charm/src/untracked.luau
View file

@ -1,36 +0,0 @@
local core = require("./core")
local setCurrentSub = core.setCurrentSub
local setCurrentScope = core.setCurrentScope
local getCurrentSub = core.getCurrentSub
local getCurrentScope = core.getCurrentScope
local function handleUntracked(
prevSub: core.ReactiveNode?,
prevScope: core.Effect | core.EffectScope?,
ok: boolean,
...
)
if prevSub then
setCurrentSub(prevSub)
elseif prevScope then
setCurrentScope(prevScope)
end
if ok then
return ...
else
error((...))
end
end
local function untracked<Args..., Results...>(callback: (Args...) -> Results..., ...: Args...): Results...
if getCurrentSub() then
return handleUntracked(setCurrentSub(nil), nil, pcall(callback, ...))
elseif getCurrentScope() then
return handleUntracked(nil, setCurrentScope(nil), pcall(callback, ...))
else
return callback(...)
end
end
return untracked