Class signals
Handling of signals.
 This can not be used as a standalone class, but is instead referenced
 explicitely in the classes, where it can be used. In the respective classes,
 it then can be used via classname:connect_signal(...) etc.
Methods
| signals:connect_signal (name, func) | Add a signal. | 
| signals:disconnect_signal (name, func) | Remove a signal. | 
| signals:emit_signal (name[, ...]) | Emit a signal. | 
Methods
- signals:connect_signal (name, func)
- 
    Add a signal.
    - name string A signal name.
- func func A function to call when the signal is emitted.
 
- signals:disconnect_signal (name, func)
- 
    Remove a signal.
    - name string A signal name.
- func func A function to remove.
 
- signals:emit_signal (name[, ...])
- 
    Emit a signal.
    - name string A signal name.
- ... Various arguments. (optional)