stacks-composables

# Stacks composables Choose the execution surface before copying a composable signature. An STX client script, an explicitly imported `@stacksjs/composables` module, and a server script can expose similarly named functions with different contracts. Read [BROWSER.md](BROWSER.md) for template delivery, forms and motion examples. ## Eager window aliases The following markers describe only explicit eager `window.name` aliases in `getCachedSignalsRuntime()`. They are checked by `core/composables/tests/skill-runtime-globals.test.ts`, and are not the whole compiler-delivered client surface. <!-- auto-imported:begin - checked against the stx runtime by core/composables/tests/skill-runtime-globals.test.ts. These are the names `getCachedSignalsRuntime()` attaches to `window`, which is what decides whether a bare call resolves in a template. Do not derive this list from `browser-auto-imports.json`: that manifest is compile-time only, and 22 of the 27 `use*` it declares are absent from the runtime. --> `useAsync`, `useClickOutside`, `useColorMode`, `useCounter`, `useDark`, `useDebounce`, `useDebouncedValue`, `useEventListener`, `useFetch`, `useFocus`, `useHead`, `useInterval`, `useLocalStorage`, `useMutation`, `useQuery`, `useRef`, `useRoute`, `useSearchParams`, `useSeoMeta`, `useSessionStorage`, `useStore`, `useThrottle`, `useTimeout`, `useToggle`, `useWebSocket`. <!-- auto-imported:end --> Additional STX names are exposed through `window.stx` and compiler destructuring, or bundled from STX composables on demand. In current STX, `useMediaQuery` and `usePreferredReducedMotion` use the first path; `useForm`, `useScroll`, `useMouse`, `useParallax`, and `useIntersectionObserver` use the demand path. These client-script names do not come from the ambient `browser-auto-imports.json` manifest. ## Explicit module imports The module surface lives in `core/composables/src/index.ts`. Import every binding in a TypeScript module even if a template entry can use it bare. ```ts import { useCounter } from '@stacksjs/composables' const counter = useCounter(0, { min: 0, max: 10 }) counter.inc() const value = counter.count.value ``` Module composables use object `Ref` values from STX: read/write `.value`, subscribe where provided, and use the exported cleanup/control functions. Template signals use `count()`, `.set()`, and `.update()`. Passing a callable signal into a module helper expecting a `Ref` is not an implicit conversion. | Task | Explicit module exports | |---|---| | State/storage | useCounter, useToggle, useStorage, useLocalStorage, history helpers | | Async/data | useFetch, createFetch, useQuery, useMutation, createQueryClient, useAsyncState | | Forms/consent | useForm, useCookieConsent | | DOM/input | useFocus, useEventListener, onClickOutside, observers, useScroll, useMouse | | Timing/watch | useIntervalFn, useTimeoutFn, useTimeoutPoll, watchDebounced, watchPausable | | Media/device | useMediaQuery, usePreferredReducedMotion, useGeolocation, useDeviceOrientation | | Browser facilities | clipboard, permissions, fullscreen, workers, virtual lists, sharing | Inspect the barrel and the individual implementation for other exports rather than installing a second library for a feature Stacks already has. ## Module query cache `useQuery({ queryKey, queryFn, staleTime, enabled, client })` provides Ref data/error/loading state, in-flight deduplication and `refetch()`. `queryFn` receives an AbortSignal. `createQueryClient({ gcTime })` provides scoped clients, `get`, `set`, `invalidate`, `gc`, and `clear`. Invalidation accepts prefix keys or a predicate matcher. Optional `refetchOnFocus` and `refetchOnReconnect` refetch stale data. Use `unsubscribe()` when the consumer ends. For template runtime queries read the STX contract in [BROWSER.md](BROWSER.md); their signatures differ. ## Module forms and consent Explicit `useForm({ initialValues, schema, onSubmit, validateOn })` accepts Stacks validators, exposes Ref values plus `field(name)` accessors, dirty/touched state, accessible `inputProps()`, `submitButtonProps()`, and server-error `setErrors()`. Apply a returned 422 map explicitly; fetching an error does not automatically attach it to a form. Field arrays and a progressive HTML fallback are not established by the primitive alone. `useCookieConsent({ policyVersion, storageKey, onChange })` stores a versioned decision. Necessary consent is always enabled; optional categories default to declined. `accept`, `acceptAll`, `declineAll`, and `withdraw` change it; `allows(category)` gates loading. A changed policy version asks again, blocked storage falls back to no stored decision, and returned visitor consent is independent of a signed-in session. Import this helper explicitly. ## Gotchas - Browser capability availability and permission denial are runtime states, even when a helper imports successfully during SSR. - Client observers/listeners need teardown. Read the selected helper's return shape; `stop`, `remove`, and `unsubscribe` are not interchangeable names. - Module `useTimeout(ms)` returns a Ref unless controls are requested; browser runtime `useTimeout(callback, delay)` runs a callback. Module counter methods are `inc`/`dec`, never `increment`/`decrement`. - Typechecking an ambient name proves neither its delivery nor its contract. Exercise a rendered template with the installed STX version. ## Source and evidence `core/composables/src/index.ts`, individual source files, and retained `tests/use-query.test.ts`, `tests/use-form.test.ts`, `tests/use-cookie-consent.test.ts` and `tests/skill-runtime-globals.test.ts` are authoritative (core paths relative to `storage/framework/`).