Coffeescript: Remove duplicate values from json object -


i new coffee script. know might silly. don't know how it.

i have json object. may have duplicate objects. how can remove duplicates , keep unique objects only.

    [object, object, object, object]     0: object     $$hashkey: "045"     id: "2"     user: "mark"     __proto__: object     1: object     $$hashkey: "046"     id: "3"     user: "jason"     __proto__: object     2: object     $$hashkey: "047"     id: "4"     user: "holmes"     __proto__: object     3: object     $$hashkey: "048"     id: "5"     user: "peter"     __proto__: object     4: object     $$hashkey: "04d"     id: "4"     user: "holmes"     __proto__: object     length: 5     __proto__: array[0]

fyi : $$hashkey not part of json. when console see it.
please help, thanks

deduplication based on id in "pure" coffeescript:

rows = [   {id: "3", user: "jason"}   {id: "4", user: "holmes"}   {id: "4", user: "holmes"}   {id: "5", user: "peter"} ]  dedup = (value _,value of new -> @[item.id] = item item in rows; @) #                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ #                          create new associative array (well ... "object")  #                          using `item.id` key. duplicates #                          overwrite previous value key -- #                          should idempotent if `id` proper key. console.log dedup

producing:

[ { id: '3', user: 'jason' },   { id: '4', user: 'holmes' },   { id: '5', user: 'peter' } ]

if don't "inline object creation", , if runtime supports array.reduce might alternative:

dedup =   (value _,value of rows.reduce ((arr,value) -> arr[value.id] = value; arr),{})

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