Redux step to step - reactjs

Question

i have this code from https://jsbin.com/zirugiteju/edit?js,console,output
but i have a question, what is {store.getState().todos} its in the bottom of the code, see please this part
const render = () => {
ReactDOM.render(
this is the code complete
const todo = (state, action) => {
switch(action.type) {
case 'ADD_TODO':
console.log("ADD");
return {
id : action.id,
text: action.text,
completed: false
};
break;
case 'TOGGLE_TODO':
if (state.id !== action.id ) {
return state;
}
return {
...state,
completed: !state.completed
};
break;
default:
return state;
}
};
const todos = (state=[], action) => {
switch(action.type) {
case 'ADD_TODO':
return [
...state,
todo(undefined, action)
];
break;
case 'TOGGLE_TODO':
return state.map(t =>todo(t, action));
break;
default:
return state;
}
};
const visibilityFilter = (state='SHOW_ALL', action) => {
switch (action.type) {
case 'SET_VISIBILITY_FILTER':
return action.filter;
break;
default:
return state;
}
};
const { combineReducers } = Redux;
const todoApp = combineReducers({
todos,
visibilityFilter
});
const { createStore } = Redux;
const store = createStore(todoApp);
const { Component } = React;
let nextTodoId = 0;
class TodoApp extends Component {
render() {
return (
<div>
<input ref={node => {
this.input = node
}} />
<button onClick={()=>{
store.dispatch({
type: 'ADD_TODO',
text: this.input.value,
id : nextTodoId++
});
this.input.value = '';
}}>
Add Todo</button>
<ul>
{this.props.todos.map(todo =>
<li key={todo.id}>
{todo.text}
</li>
)}
</ul>
</div>
);
}
}
const render = () => {
ReactDOM.render(
<TodoApp
todos={store.getState().todos}
/>,
document.getElementById('root')
);
};
store.subscribe(render);
render();

Answer 1

The prop todos = {store.getState().todos} that you are passing to TodoApp component is a reducer, called todos, from your redux state that you combined in this part of the code:
const todoApp = combineReducers({
todos,
visibilityFilter
});
The getState() function returns the current state tree of your application. It is equal to the last value returned by the store's reducer.
You can learn more about redux States in this link: https://redux.js.org/api/store