dynamic_nested.exs

# my blog  : https://trangell.com/fa/
# public : http://iranonrails.ir
nested = %{
    buttercup: %{ 
      actor: %{
        first: "Robin",
        last:  "Wright"
      },
      role: "princess"
    },
    westley: %{
      actor: %{
        first: "Cary",
        last:  "Ewles"     # typo!
      },
      role: "farm boy"
    }
}

IO.inspect get_in(nested, [:buttercup])
# => %{actor: %{first: "Robin", last: "Wright"}, role: "princess"}

IO.inspect get_in(nested, [:buttercup, :actor])
# => %{first: "Robin", last: "Wright"}

IO.inspect get_in(nested, [:buttercup, :actor, :first])  
# => "Robin"

IO.inspect put_in(nested, [:westley, :actor, :last], "Elwes")
# => %{buttercup: %{actor: %{first: "Robin", last: "Wright"}, role: "princess"},
# =>     westley: %{actor: %{first: "Cary", last: "Elwes"}, role: "farm boy"}}



get_in
put_in
update_in
get_and_update_in