The trick obviously is doing it without forcing DF to wait suspended.
Fortunately, lua has built-in coroutine support, so the interactive
prompt can simply yield and rely on the external loop to do the job.
To use this however the REPL had to be replaced with lua code.
- This context requires core suspend lock and asserts it in a few places.
- Special 'event' objects are introduced. They can be invoked as
functions, in which case they iterate all their fields and call
them as functions. Errors are printed and consumed.
- When a plugin is opened by the core context, events registered in
a special array are linked to it. The system is organized so as to
avoid even trying to pass the event to lua if the module isn't loaded.
- To ensure reload safety functions have to be wrapped. Every call
checks the loaded state and locks a mutex in Plugin. If the plugin
is unloaded, calling its functions throws a lua error. Therefore,
plugins may not create closures or export yieldable functions.
- The set of function argument and return types supported by
LuaWrapper is severely limited when compared to being compiled
inside the main library.
Currently supported types: numbers, bool, std::string, df::foo,
df::foo*, std::vector<bool>, std::vector<df::foo*>.
- To facilitate postponing initialization until after all plugins
have been loaded, the core sends a SC_CORE_INITIALIZED event.
- As an example, the burrows plugin now exports its functions.
Supports two modes of finalization:
- try {...} finally {...}
- try {...} catch { ...; throw }
Argument passing discipline is designed with vararg tail calls in mind.
Alexander Gavrilov