javascript - Get the set of all possible values for a categoric field -


this question has answer here:

from following object 

items = [{     title = 'title 1',     category = 'foo'   },   {     title = 'title 5',     category = 'bar'   },   {     title = 'title n',     category = 'bar'   }, ]

which

  • i receive dynamically @ runtime
  • can have length
  • where each category field can have 1 of items.length values

i want set of different values field category.

in example above, result of 

get_all_possible_categories(items)

would be

['foo','bar'].

how can implement 

get_all_possible_categories(items) ?

just map values array, using set unique values

items = [{      title : 'title 1',      category : 'foo'    },    {      title : 'title 5',      category : 'bar'    },    {      title : 'title n',      category : 'bar'    }  ];    function get_all_possible_categories(arr) {    return [...new set(arr.map( x => x.category))];  }    var result = get_all_possible_categories(items);    console.log(result);


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