Mar 31, 2026 · Fundamentals

Why Using = in Python Can Delete Your Data: Common Copy Pitfalls Explained

The article reveals how the Python assignment operator creates references instead of copies, leading to accidental data loss, and walks through safe copying techniques (.copy(), list(), [:]) with concrete examples, performance benchmarks, and guidance for nested structures.

Performance BenchmarkPythonassignment

0 likes · 8 min read

Why Using = in Python Can Delete Your Data: Common Copy Pitfalls Explained

MaGe Linux Operations

Nov 28, 2019 · Fundamentals

Why Python’s [:] List Copy Is Misleading and Better Alternatives

Python’s slice syntax new = old[:] appears to copy a list, but it actually creates a reference to the same object, leading to subtle bugs; this article explains Python’s object model, demonstrates the pitfalls, and presents clearer alternatives such as list(), copy.copy(), and deepcopy.

Slicebest-practicesdeep copy

0 likes · 6 min read

Why Python’s [:] List Copy Is Misleading and Better Alternatives