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36 lines
1.3 KiB
Markdown
36 lines
1.3 KiB
Markdown
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# Object model for Python analysis
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## General idea
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Each 'object' in the analysis represents a static approximation to a set of objects in the actual program.
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For objects like classes and functions there is a (mostly) one-to-one correspondence.
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For instances, bound-methods and other short lived objects, one entity in the analysis represents a set of similar objects.
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## APIs
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Objects have two APIs; an internal and a user-facing API.
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### Internal API
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The internal API, exposed through `ObjectInternal` class, provides the predicates necessary for points-to to infer the behaviour of the object. This covers a number of operations:
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* Truth tests
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* Type tests and type(x) calls
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* Attribute access
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* Calls
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* Subscripting
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* Descriptors
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* Comparing objects
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* Treating the object as an integer or a string
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Part of internal API exists to allow other objects to implement the points-to facing part of the API.
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For example, behaviour of a (Python) class will determine the behaviour of instances of that class.
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### User-facing API
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The user-facing API, exposed through `Value` class, provides a higher level API designed for writing queries rather
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than implementing points-to. It provides easy access to objects by name and the ability to find calls to, attributes of, and references to objects.
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