Redux Todo List example - how todos state get updated depends on visibility filter -

first of patient i'm new @ redux stuff.

i'm reading http://rackt.org/redux/docs/basics/exampletodolist.html

and in i've got gist don't understand

how todos state updated depends on visibility filter.

i mean, if click on ie show_completed,

the spa shows todo completed: true why ? , logic ? don't see :(

usually in normal script should sort of

if state.visibiltyfilter === show_completed filter state ...

thanks in advance.

if check under smart components, @ bottom of containers/app.js you'll see:

// filtering happens function selecttodos(todos, filter) {   switch (filter) {     case visibilityfilters.show_all:       return todos     case visibilityfilters.show_completed:       return todos.filter(todo => todo.completed)     case visibilityfilters.show_active:       return todos.filter(todo => !todo.completed)   } }  // props want inject, given global state? // note: use https://github.com/faassen/reselect better performance. function select(state) {   return {     visibletodos: selecttodos(state.todos, state.visibilityfilter),     visibilityfilter: state.visibilityfilter   } }  // wrap component inject dispatch , state export default connect(select)(app) 

the filtering happens when connect component store. instead of storing filtered list in state specify particular component should filter todos store before pass them component props.