Editing Openai/694590c5-f52c-800f-9af6-d10143a2d812 (section)

=== Assistant: You’re looping because one sentence is still wrong in your head. ===
You’re looping because one sentence is still wrong in your head. I’ll fix it cleanly and mechanically.

==== - ❌ It does not dispatch actions ====
* ❌ It does not forward actions to other slices
* ❌ It does not “fix” cross-slice execution

extraReducers does nothing special at runtime.

==== Because Redux itself calls all slice reducers for every dispatched action. ====

This is the part you were missing.

==== When you do: ====

<syntaxhighlight lang="ts">dispatch(userLoggedOut())

</syntaxhighlight>

Redux does internally (simplified):

<syntaxhighlight lang="ts">rootReducer(state, action)

</syntaxhighlight>

And rootReducer is basically:

<syntaxhighlight lang="ts">{
  auth: authReducer(state.auth, action),
  posts: postsReducer(state.posts, action),
  users: usersReducer(state.users, action),
}

</syntaxhighlight>

➡️ Every slice reducer is called
➡️ Not optional
➡️ Not related to extraReducers

==== Each slice reducer checks: ====

<syntaxhighlight lang="ts">if (action.type === 'auth/userLoggedOut') {
  run matching case
}

</syntaxhighlight>

Now:
* authSlice has addCase(userLoggedOut) → match → runs
* postsSlice has addCase(userLoggedOut) → match → runs

Same action. Same type. Two reducers react.

No dispatching between slices.
No forwarding.
No chaining.

==== It fixes action ownership, not execution. ====

===== You would do this (WRONG): =====

<syntaxhighlight lang="ts">postsSlice.reducers = {
  userLoggedOut() { ... }
}

</syntaxhighlight>

This creates:

<syntaxhighlight lang="ts">{ type: 'posts/userLoggedOut' }

</syntaxhighlight>

Which does not match:

<syntaxhighlight lang="ts">{ type: 'auth/userLoggedOut' }

</syntaxhighlight>

So logout breaks.

==== Because it lets a slice say: ====

: 

That’s it.

==== 1. Dispatch happens ONCE ====
# Redux calls ALL slice reducers
# Reducers match on exact <code>action.type</code>
# <code>reducers</code> = create + handle
# <code>extraReducers</code> = handle only

extraReducers does not enable cross-slice execution.
Redux’s root reducer does.

Once you separate those two ideas, the confusion disappears permanently.