Contracts for C: A Proof of Concept

2025-09-09
Contracts for C: A Proof of Concept

This article explores bringing the concept of contracts from C++ to the C language. The author proposes a solution using `contract_assert` and `contract_assume` macros for precondition and postcondition checks respectively. The `defer` macro and C23's `unreachable` macro simplify postcondition expression. The article demonstrates how inline functions and helper functions can add contract checks without altering core function implementations, leveraging compiler optimizations. While further interface specification refinement is needed, this article provides a viable proof of concept for contracts in C.

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