Derive Macro LuaUserData 

#[derive(LuaUserData)]
{
    // Attributes available to this derive:
    #[lua]
    #[lua_impl]
}

Derive UserDataTrait for a struct or enum.

Supported field types (auto-converted to/from UdValue)

• i8..i64, isize → UdValue::Integer
• u8..u64, usize → UdValue::Integer
• f32, f64 → UdValue::Number
• bool → UdValue::Boolean
• String → UdValue::Str

Field attributes

• #[lua(skip)] — exclude from Lua
• #[lua(readonly)] — get only, no set
• #[lua(name = "...")] — custom Lua name

Struct attributes

• #[lua_impl(Display, PartialEq, PartialOrd)] — metamethods from Rust traits

Enum behavior

• C-like enums also implement LuaEnum, so they can be exported with register_enum::<T>()
• Enums with payloads are treated as fieldless userdata and can expose methods via #[lua_methods]

Conversion behavior

• IntoLua is auto-implemented, so derived userdata values can be passed directly into typed APIs
• Owned FromLua is intentionally not auto-implemented, because userdata lives in Lua GC storage and implicit extraction by value would blur ownership semantics

Example

#[derive(LuaUserData, PartialEq, PartialOrd)]
#[lua_impl(Display, PartialEq, PartialOrd)]
struct Point {
    pub x: f64,
    pub y: f64,
    #[lua(skip)]
    internal_id: u32,
}