Creating a SaveableObject

At the heart of saveable-objects lies the class SaveableObject. There are several ways to create a SaveableObjects which we will outline here:

1. Inheritance

2. Decorating

3. Wrapping

Throughout this tutorial we will consider converting the class

class A():
    pass

to a saveable-object.

Inheritance

You can design a class to be a saveable-object from the ground up via inheritance. To achieve this you must do two things:

1. Inherit SaveableObject

2. Add path as a keyword arguement to the __init__ function:

For example,

from saveable_objects import SaveableObject

class A(SaveableObject):
    def __init__(self, path: Optional[str] = None):
        super().__init__(path)

Note if you forget step 2., i.e., For example,

from saveable_objects import SaveableObject

class A(SaveableObject):
    def __init__(self):
        super().__init__("fixed_path.pkl")

the code will crash. This is because the path variable is intercepted from

Decorating

A less intrusive but less transparent method is to decorate the definition of A with SaveableWrapper:

from saveable_objects.extensions import SaveableWrapper

@SaveableWrapper
class A():
    pass

We can also pass a default path as follows:

from saveable_objects.extensions import SaveableWrapper

@SaveableWrapper(path="default_path.pkl")
class A():
    pass

Note that under the hood this will result in a slightly different inheritance structure than achieved via the inheritance method. Specifically the decorator generates a new class that will be called A that inherits the old A and SaveableObject.

Wrapping

Sometimes you might import A from a package or other code you don’t wish to modify. A consise solution to this is to wrap the class A using SaveableWrapper:

from saveable_objects.extensions import SaveableWrapper

A = SaveableWrapper[A];

We can also pass a default path as follows:

from saveable_objects.extensions import SaveableWrapper

A = SaveableWrapper(path="default_path.pkl")[A];

Note, just as with decoration method, under the hood this will result in a slightly different inheritance structure than achieved via the Inheritance method. Specifically the decorator generates a new class that will be called A that inherits the old A and SaveableObject.

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