earwax.mixins module

Provides various mixin classes for used with other objects.

class earwax.mixins.DismissibleMixin(dismissible: bool = True)

Bases: object

Make any Level subclass dismissible.

Variables:dismissible – Whether or not it should be possible to dismiss this level.
dismiss() → None

Dismiss the currently active level.

By default, when used by earwax.Menu and earwax.Editor, this method is called when the escape key is pressed, and only if self.dismissible evaluates to True.

The default implementation simply calls pop_level() on the attached earwax.Game instance, and announces the cancellation.

class earwax.mixins.DumpLoadMixin

Bases: object

A mixin that allows any object to be dumped to and loaded from a dictionary.

It is worth noting that only instance variables which have type hints (and thus end up in the __annotations__ dictionary) will be dumped and loaded.

Also, any instance variables whose name starts with an underscore (_) will be ignored.

To dump an instance, use the dump() method, and to load, use the load() constructor.

The __allowed_basic_types__ list holds all the types which will be dumped without any modification.

By default, the only collection types that are allowed are list, and dict.

If you wish to exclude attributes from being dumped or loaded, create a __excluded_attributes__ list, and add all names there.

dump() → Dict[str, Any]

Dump this instance as a dictionary.

classmethod from_file(f: TextIO, *args) → Any

Return an instance from a file object.

Parameters:
  • f – A file which has already been opened.
  • args – Extra positional arguments to pass to the load constructor.
classmethod from_filename(filename: pathlib.Path, *args) → Any

Load an instance from a filename.

Parameters:filename – The path to load from.
get_dump_value(type_: Type[CT_co], value: Any) → Any

Get a value for dumping.

Parameters:value – The value that is present on the instance.
classmethod get_load_value(expected_type: Type[CT_co], value: Any) → Any

Return a loaded value.

In the event that the dumped value represents a instance of earwax.mixins.DumpLoadValue, the dictionary must have been returned by earwax.mixins.DumpLoadMixin.dump(), so it contains both the dumped value, and the type annotation.

This prevents errors with Union types representing multiple subclasses.

If the type of the provided value is found in the __allowed_basic_types__ list, it will be returned as-is. This is also true if the value is an enumeration value.

If the type of the provided value is list, then each element will be passed through this method and a list of the loaded values returned.

If the type of the value is dict, one of two things will occur:

  • If expected_type is also a dict, then the given value will have
    its keys and values loaded with this function.
  • If expected_type is also a subclass of
    earwax.mixins.DumpLoadMixin, then it will be loaded with that class’s load method.
  • If neither of these things are true, RuntimeError will be raised.
Parameters:
  • expected_type – The type from the __annotations__ dictionary.
  • value – The raw value to load.
classmethod load(data: Dict[str, Any], *args) → Any

Load and return an instance from the provided data.

It is worth noting that only keys that are also found in the __annotations__ dictionary, and not found in the __excluded_attribute_names__ list will be loaded. All others are ignored.

Parameters:
  • data – The data to load from.
  • args – Extra positional arguments to pass to the constructor.
save(filename: pathlib.Path) → None

Write this object to the provided filename.

Parameters:filename – The path to the file to dump to.
class earwax.mixins.RegisterEventMixin

Bases: object

Allow registering and binding events in one function.

register_and_bind(func: EventType) → EventType

Register and bind a new event.

This is the same as:

level.register_event_type('f')

@level.event
def f() -> None:
    pass
Parameters:func – The function whose name will be registered, and which will be bound to this instance.
register_event(func: EventType) → str

Register an event type from a function.

This function uses func.__name__ to register an event type, eliminating possible typos in event names.

Parameters:func – The function whose name will be used.
class earwax.mixins.TitleMixin(title: Union[str, TitleFunction])

Bases: object

Add a title to any Level subclass.

Variables:title –

The title of this instance.

If this value is a callable, it should return a string which will be used as the title.
get_title() → str

Return the proper title of this object.

If self.title is a callable, its return value will be returned.