How close can pure FP get to C?
Summary
This article benchmarks pure functional languages Lean 4 and Roc against C for a DEFLATE compression task, showing Roc can approach C performance on non-streaming paths while preserving memory safety and determinism. It discusses the trade-offs between safety and speed, outlines Roc specific optimizations, and highlights the potential and limits of pure FP approaches before suggesting future exploration and improvements.