How do I check between 2 arrays of different objects?

Question

I want to check if a claim's items has assets in it and @item_assets basically gets all the items in the database that are classified as assets.

When doing the following:

>> @claim.items
=> [#<Item id: 8, name: "chair", amount: 10.0, gst: 0.7, override: false, item_category_id: 7, item_expense_id: 8, claim_id: 8, club_id: 71, created_at: "2009-10-18 10:16:10", updated_at: "2009-10-18 10:16:10">, #<Item id: 9, name: "soemthing", amount: 20.0, gst: 1.4, override: false, item_category_id: 7, item_expense_id: 7, claim_id: 8, club_id: 71, created_at: "2009-10-18 10:16:10", updated_at: "2009-10-18 10:16:10">]

>> @items_assets
=> [#<Item id: 8, name: "chair", amount: 10.0, gst: 0.7, override: false, item_category_id: 7, item_expense_id: 8, claim_id: 8, club_id: 71, created_at: "2009-10-18 10:16:10", updated_at: "2009-10-18 10:16:10">, #<Item id: 9, name: "soemthing", amount: 20.0, gst: 1.4, override: false, item_category_id: 7, item_expense_id: 7, claim_id: 8, club_id: 71, created_at: "2009-10-18 10:16:10", updated_at: "2009-10-18 10:16:10">]

>> @claim.items.include? @items_assets
=> false

The result puzzles me. After investigation I realize that the items on both arrays are of different object even though they refer to the same id.

As such, it appears that include? can no longer work in this case.

Can someone suggest how else should I go about checking if a claim's items have assets in it?

Claim HM Items
Items BT Claim

Answer 1

@claim.items.include? @items_assets

What you're asking here is "Does the array @claim.items contain an element equal to the @item_assets object?"

What you seem to want to ask is "Does the array @claim.items contain an element equal to any element in another array, @item_assets?"

@claim.items != @claim.items - @item_assets would return true if any element in @item_assets matched any element in @claim.items, but the performance of doing that will likely be terrible.

I would look at storing your @item_assets in a Set, assuming you really do want to yank them all into memory. Then checks to see if your @claim.items elements appear in that Set will be much faster.