I have an array of ids order say
order = [5,2,8,6]
and another array of hash
[{id: 2,name: name2},{id: 5,name: name5}, {id: 6,name: name6}, {id: 8,name: name8}]
I want it sorted as
[{id: 5,name: name5},{id: 2,name: name2}, {id: 8,name: name8}, {id: 6,name: name6}]
What could be best way to implement this? I can implement this with iterating both and pushing it to new array but looking for better solution.
Try this
arr = [
{:id=>2, :name=>"name2"}, {:id=>5, :name=>"name5"},
{:id=>6, :name=>"name6"}, {:id=>8, :name=>"name8"}
]
order = [5,2,8,6]
arr.sort_by { |a| order.index(a[:id]) }
# => [{:id=>5, :name=>"name5"}, {:id=>2, :name=>"name2"},
#{:id=>8, :name=>"name8"}, {:id=>6, :name=>"name6"}]
Starting from Rails 7, there is a new method Enumerable#in_order_of.
A quote right from the official Rails docs:
in_order_of(key, series)
Returns a new
Arraywhere the order has been set to that provided in theseries, based on thekeyof the objects in the original enumerable.
[ Person.find(5), Person.find(3), Person.find(1) ].in_order_of(:id, [ 1, 5, 3 ])
=> [ Person.find(1), Person.find(5), Person.find(3) ]
If the
seriesinclude keys that have no corresponding element in theEnumerable, these are ignored. If theEnumerablehas additional elements that aren't named in theseries, these are not included in the result.
It is not perfect in a case of hashes, but you can consider something like:
require 'ostruct'
items = [{ id: 2, name: 'name2' }, { id: 5, name: 'name5' }, { id: 6, name: 'name6' }, { id: 8, name: 'name8' }]
items.map(&OpenStruct.method(:new)).in_order_of(:id, [5,2,8,6]).map(&:to_h)
# => [{:id=>5, :name=>"name5"}, {:id=>2, :name=>"name2"}, {:id=>8, :name=>"name8"}, {:id=>6, :name=>"name6"}]
Sources:
