10 lines
553 B
Plaintext
10 lines
553 B
Plaintext
py-AddOn classes are like dynamic mixins, but with their own private attribute
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and method namespaces. A concern implemented using add-ons can be added at
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runtime to any object that either has a writable __dict__ attribute, or is
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weak-referenceable.
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AddOn classes are also like adapters, but rather than creating a new instance
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each time you ask for one, an existing instance is returned if possible. In
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this way, add-ons can keep track of ongoing state. For example, a Persistence
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add-on might keep track of whether its subject has been saved to disk.
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