Redux - I don't understand "Task-Based Updates" example -


in link: task-based updates don't understand below code:

import posts "./postsreducer"; // missing code?? import comments "./commentsreducer"; // missing code??

and why should that?

const combinedreducer = combinereducers({     posts,     comments });  const rootreducer = reducereducers(     combinedreducer,     featurereducers );

only featurereducers okie? not need combindedreducer? anh postsreducer code, commentsreducer code?

thanks helps!

unfortunately example little confusing (one of few places in solid redux docs). if go here , check out 'third approach', you'll see concept explained little better.

essentially, postreducer , commentreducer there handle actions modify posts or comments--that is, things not require changes multiple tables (e.g posts , comments). featurereducer task-based reducer handles actions require updates multiple tables.

a simplified example:

const postreducer = (state = {}, action) => {   return state }  const commentreducer = (state = {}, action) => {   return state }  const combined = combinereducers({   posts: postreducer,   comments: commentreducer })  const createcomment = (state, action) => {   switch(action.type) {     case 'create_comment':       // update multiple tables (linked example ok job ok demonstrating this)       return updatedstate      default:       return state;   } }  const rootreducer = reducereducers( combined, createcomment )

in example, first 2 reducers create state shape. third, depends on first 2 set state it, updates multiple tables across redux store.

your state shape this:

{   posts: {},   comments: {} }

if you're confused reducereducers, try think of combinereducers, doesn't affect state shape.


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