# Hot Reload

Replace a module's code at runtime without destroying the engine or losing registered types.

## Basic Reload

```cpp
const char* new_src = R"(
    int32 main() {
        println("updated version!");
        return 2;
    }
)";
bool ok = reload(mod, new_src, strlen(new_src), "script.em");
```

## Running the New Code

Existing contexts pick up the new code on the next `execute()` call, no need to recreate them:

```cpp
execute(ctx, "main");                        // runs v1
reload(mod, new_src, len, "script.em");
execute(ctx, "main");                        // runs v2 on the same ctx
```

## Typical Hot Reload Loop

```cpp
module_t* mod = compile_file(e, "game.em");
context_t* ctx = create_context(mod);

while (running) {
    if (file_changed("game.em")) {
        std::string src = read_file("game.em");
        reload(mod, src.c_str(), src.size(), "game.em");
    }
    execute(ctx, "update");
}
```

Globals, registered types, and native functions persist; only the script code is replaced.


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