how to create an array of hashes by looping over array of objects

Question

I have following array of hash. I am trying to loop over it and build an array of hash of values of id and product_order_id.

objects = 
[
  #<Product: 0x00007ffd4a561108
  @id="1",
  @product_id="2",
  @product_order_id="23",
  @description="abc",
  @status="abcde",
  @start_date=nil,
  @end_date=nil>,
  #<Product: 0x00007ffd4a560c80
  @id="45",
  @product_id="22",
  @product_order_id="87",
  @description="ahef",
  @status="gesff",
  @start_date=nil,
  @end_date=nil>
......more objects.....
    ]

This is what it should look like

[{ "1": "23" }, { "45": "87" }] -->its going to be uuid

I tried doing this but no luck

def mapped_product(objects)
    mapping = []
    objects.each do |object|
      mapping << {
        object.product_order_id: object.id
      }
    end
end

Any idea?

Don't you mean it should look like [{ 1=>23 }, { 45=>87 }], as symbol names cannot begin with a digit? — Cary Swoveland
– Cary Swoveland, Commented Dec 4, 2018 at 3:49
A quick question, why do you want an array containing hashes that have only one key/value pair? It seems to me that { '1' => '23', '45' => '87' } (one hash without wrapped array) is a better result. — 3limin4t0r
– 3limin4t0r, Commented Dec 4, 2018 at 15:43
The array of hash is not going to be just have 2 values, it could have 100 or 500 objects — jose miliano
– jose miliano, Commented Dec 4, 2018 at 15:56

Gagan Gami · Accepted Answer · 2018-12-04 06:37:55Z

1

inline solution:

> Hash[objects.map{|p| [p.id, p.product_order_id] }]
# Output : [{ 1=>23 }, { 45=>87 }]

answered Dec 4, 2018 at 6:37

Gagan Gami

10.3k1 gold badge32 silver badges56 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Mereghost · Accepted Answer · 2018-12-04 11:24:12Z

1

I'd usually implement it using an each_with_object

objects.each_with_object({}) { |obj, acc| acc[obj.id] = obj.product_order_id }

Unless I reaaaly want to squeeze some performance, than I'd go with Gagan's answer

answered Dec 4, 2018 at 11:24

Mereghost

6884 silver badges8 bronze badges

Comments

nicosantangelo · Accepted Answer · 2018-12-04 02:19:14Z

0

Have you tried this?

def mapped_product(objects)
    mapping = []
    objects.each do |object|
      mapping << {
        object.id => object.product_order_id # I'm using an `=>` here
      }
    end
    mapping # return the new mapping
end

I've just changed the : on the hash for a => to "make it dynamic" and swapped the values of id and product_order_id

You can also use a map here:

def mapped_product(objects)
    objects.map do |object|
     {  object.id => object.product_order_id }
    end
end

answered Dec 4, 2018 at 2:19

nicosantangelo

13.8k3 gold badges35 silver badges47 bronze badges

Collectives™ on Stack Overflow

how to create an array of hashes by looping over array of objects

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related