docs(combine): add object constraints to T and U in signature

[hyun907]

Related Bug Reports or Discussions

N/A — found via source/docs signature audit, matching the convention recently applied in #3491, #3492, #3493.

Summary

The combine signature in docs/reference/middlewares/combine.md is missing the extends object constraints on T and U that exist in the source.

Current docs signature:

combine<T, U>(
  initialState: T,
  additionalStateCreatorFn: StateCreator<T, [], [], U>,
): StateCreator<Omit<T, keyof U> & U, [], []>

Source signature in src/middleware/combine.ts:

export function combine<
  T extends object,
  U extends object,
  Mps extends [StoreMutatorIdentifier, unknown][] = [],
  Mcs extends [StoreMutatorIdentifier, unknown][] = [],
>(
  initialState: T,
  create: StateCreator<T, Mps, Mcs, U>,
): StateCreator<Write<T, U>, Mps, Mcs>

Without the constraints, the docs imply that combine accepts primitives for initialState.

For example, combine({ count: 0 }, ...) works, while combine(0, ...) is rejected by the source's T extends object constraint.

This matches the existing convention in docs/reference/middlewares/redux.md, which preserves the source's A extends { type: string } constraint in its signature.

Diff

- combine<T, U>(initialState: T, additionalStateCreatorFn: StateCreator<T, [], [], U>): StateCreator<Omit<T, keyof U> & U, [], []>
+ combine<T extends object, U extends object>(initialState: T, additionalStateCreatorFn: StateCreator<T, [], [], U>): StateCreator<Omit<T, keyof U> & U, [], []>

Docs-only change — no changeset needed.

Check List

• pnpm run fix for formatting and linting code and docs

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