Change behaviour of Float

[neel-desh]

Hi, I just wanted to know how do I change the behavior of Float in Jason.encode!()

By default Jason.encode!(1000.0) returns "1.0e3" I want Jason.encode!(1000.0) to return "1000.0"

I tried to make this change.

  defimpl Jason.Encoder, for: Float do
    def encode!(float, _opts) do
      :erlang.float_to_binary(float, [{:decimals, 15}, :compact])
    end
  end

And I was expecting it to work! but sadly it did not. Can someone please guide me in the right direction.

Thanks

[michalmuskala]

In general overriding protocol implementations is not supported in Elixir and is largely accidental how it would work. For Jason in particular, it does not use the protocol for encoding core data types to avoid the overhead of the protocol dispatch in the regular case. This means there is generally no way to override how values are encoded, other than:

• wrapping them in a struct and implementing the protocol for that struct
• pre-encoding them with into the desired format and wrapping into Jason.Fragment.new/1 as raw JSON data to be spliced when encoding