A design-by-contract Python package in ~100 lines
Greetings! A 2.5 weekends project to teach myself newer Python features (>= 3.10). Conditions are written as Lambda expressions that annotate parameters and return types, and coexist with type annotations. Symbols to share values between conditions are also supported to a limited extend.
In plain words
This is a lightweight Python package implementing design-by-contract principles, created as a learning project for Python 3.10+ features. Developers can specify preconditions and postconditions using lambda expressions that work alongside standard type annotations, with limited support for sharing values between conditions. The package is compact at approximately 100 lines of code and demonstrates contract-based programming patterns for Python development.
written from the facts on this page · September 2026
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