Event export macro

[matcool]

Example Usage:

// (In your api distributed header file)
#pragma once
#include <Geode/loader/Dispatch.hpp>
// You must **manually** declare the mod id, as macros like GEODE_MOD_ID will not
// behave correctly to other mods using your api.
#define MY_MOD_ID "dev.my-api"

namespace api {
  // Important: The function must be declared inline, and return a geode::Result,
  // as it can fail if the api is not available.
  inline geode::Result<int> addNumbers(int a, int b) GEODE_EVENT_EXPORT(&addNumbers, (a, b));
}

Then, in one of your source files, you must define the exported functions:

// MUST be defined before including the header.
#define GEODE_DEFINE_EVENT_EXPORTS
#include "../include/api.hpp"
Result<int> api::addNumbers(int a, int b) {
  return Ok(a + b);
}