Elixir has a few forms of updating a struct (or map) %{existing_map_or_struct | some_key_1: :some_val, some_key_2: :some_val} Then there is also `put_in/2

Elixir has a few forms of updating a struct (or map) %{existing_map_or_struct | some_key_1: :some_val, some_key_2: :some_val} Then there is also `put_in/2`, `put_in/3`, `update_in/2`, `update_in/3`, these are nice because they work in pipelines some_val |> put_in([:foo, :bar, :baz], 3) some_val |> update_in([:foo, :bar, :baz], fn x -> x + 1 end) The macro forms are cool too put_in(foo.bar.baz, 2) update_in(foo[:some]["nested"][:path], & &1 + 1) The cool thing about the `/2` forms of `put_in` and `update_in` is that they are macros they rewrite the ast to return the entire object, and not just the changed value. iex(1)> foo = %{bar: %{baz: 2}} %{bar: %{baz: 2}} iex(2)> update_in(foo.bar.baz, & &1 + 1) %{bar: %{baz: 3}} There's even more powerful macros like `get_and_update_in` which can use "selectors" to extend their functionality (https://hexdocs.pm/elixir/master/Kernel.html#get_and_update_in/2 https://hexdocs.pm/elixir/master/Kernel.html#get_and_update_...) https://hexdocs.pm/elixir/master/Kernel.html#put_in/2 https://hexdocs.pm/elixir/master/Kernel.html#put_in/2 https://hexdocs.pm/elixir/master/Kernel.html#put_in/3 https://hexdocs.pm/elixir/master/Kernel.html#put_in/3 https://hexdocs.pm/elixir/master/Kernel.html#update_in/2 https://hexdocs.pm/elixir/master/Kernel.html#update_in/2 https://hexdocs.pm/elixir/master/Kernel.html#update_in/3 https://hexdocs.pm/elixir/master/Kernel.html#update_in/3