arrays - Combining filter() and map () methods in javascript -


i have been working through study guide on github , trying work through problem chains filter , map answer. so, have array , i'm supposed use 2 methods select ids of videos rating of 5.0. here's array:

function() { var newreleases = [     {         "id": 70111470,         "title": "die hard",         "boxart": "http://cdn-0.nflximg.com/images/2891/diehard.jpg",         "uri": "http://api.netflix.com/catalog/titles/movies/70111470",         "rating": 4.0,         "bookmark": []     },     {         "id": 654356453,         "title": "bad boys",         "boxart": "http://cdn-0.nflximg.com/images/2891/badboys.jpg",         "uri": "http://api.netflix.com/catalog/titles/movies/70111470",         "rating": 5.0,         "bookmark": [{ id:432534, time:65876586 }]     },     {         "id": 65432445,         "title": "the chamber",         "boxart": "http://cdn-0.nflximg.com/images/2891/thechamber.jpg",         "uri": "http://api.netflix.com/catalog/titles/movies/70111470",         "rating": 4.0,         "bookmark": []     },     {         "id": 675465,         "title": "fracture",         "boxart": "http://cdn-0.nflximg.com/images/2891/fracture.jpg",         "uri": "http://api.netflix.com/catalog/titles/movies/70111470",         "rating": 5.0,         "bookmark": [{ id:432534, time:65876586 }]     } ];

now code follows:

  newreleases.filter(function(video){     return video.rating == 5.0;   }).map (function(video) {     return { id: video.id }    }); }

my thought process first call filter method , apply test (video.rating == 5.0) , return elements pass test. use map method apply function elements passed test return want, ids of videos have 5.0 rating, having map return 'video.id'. when execute, error:

typeerror: 'undefined' not object (evaluating 'videoids.sortby')

this error code throwing me off, because don't see 'videoids' variable in array , doesn't appear need apply .sortby.

so asking clarification on error code please. have tried code in number of different fashions , have not come correct one, appreciate walk through of not doing. reason feel confident in code because have applied similar code similar exercise in [eloquent javascript] @ end of chapter 5 (exercise 5.2 mother-child age difference). have spent hours (more i'd admit) stuck on , have browsed stack overflow 2 hours. press answer button afraid won't learn doing that.

could please assist me?

please add return. otherwise undefined returning.

return newreleases.filter(function(video) {     //...

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