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Using the gist below, use the array of objects defined at the bottom of the script to answer the questions at the top of the script.

https://gist.github.com/masondesu/1eafc9e7dff1ca7666ba

Level Up

If you complete the above assignment, complete the 10 exercises here:

http://www.ling.gu.se/~lager/teaching/dialogue_systems%20II/labs/javascript.html

Power Level 9000

One of the most useful exercises I've ever done as a programmer is the following:

1. Write your own forEach function. It takes the array and the function (referred to as a callback) as arguments:

   function forEach(list, callback) { /* Do stuff */ }

2. Write your own map, reduce, and filter that use your custom forEach to do their work.

3. Write a function called pluck that extracts a list of property names:

   function pluck(list, propertyName) { /* Do stuff*/ }
   
   var stooges = [{name: 'moe', age: 40}, {name: 'larry', age: 50}, {name: 'curly', age: 60}];
   pluck(stooges, 'name');
   // => ["moe", "larry", "curly"]

4. Write a function called reject that returns the values in list without the elements that the truth test (predicate) passes. The opposite of filter.

   function reject(list, predicate) { /* Do stuff */ }
   
   var odds = reject([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
   //=> [1, 3, 5]

5. Write a function called find that looks through each value in the list, returning the first one that passes a truth test (predicate), or undefined if no value passes the test. The function returns as soon as it finds an acceptable element, and doesn't traverse the entire list.

   function find(list, predicate) { /* Do stuff */ }
   
   var even = find([1, 2, 3, 4, 5, 6], function(num){ return num % 2 == 0; });
   //=> 2

6. Write a function called where that looks through each value in the list, returning an array of all the values that contain all of the key-value pairs listed in properties.

   function where(list, properties) { /* Do stuff */ }
   
   where(listOfPlays, {author: "Shakespeare", year: 1611});
   // => [{title: "Cymbeline", author: "Shakespeare", year: 1611},
   //     {title: "The Tempest", author: "Shakespeare", year: 1611}]