Composite Macros

Rustler provides a bunch of macros for generating encoder and decoder implementations for composite data structures. These proc macros are implemented in the rustler_codegen crate.

Maps

The NifMap attribute will generate encoders and decoders from Elixir maps. Atoms are used as keys. It is used as follows:

#[derive(NifMap)]struct MyMap {    a: u32,    b: u32,}

Elixir Structs

The NifStruct attribute will generate encoders and decoders from an Elixir struct. It is mostly identical to the NifMap attribute, but also manages the :__struct__ field. It is used as follows:

#[derive(NifStruct)]#[module = "Elixir.MyStruct"]struct MyStruct {    a: u32,    b: u32,}