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arXiv · 2509.13022

Navigating the Python Type Jungle

Andrei Nacu·Dorel Lucanu
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Abstract

Python's typing system has evolved pragmatically into a powerful but theoretically fragmented system, with scattered specifications. This paper proposes a formalization to address this fragmentation. The central contribution is a formal foundation that uses concepts from type theory to demonstrate that Python's type system can be elegantly described. This work aims to serve as a crucial first step toward the future development of type inference tools.

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Andrei Nacu, Dorel Lucanu. 2025-09-16. Navigating the Python Type Jungle. https://doi.org/10.4204/eptcs.427.6

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