Haskell is the obvious answer. Rust is the bastard child of Haskell and C (my two loves). If one needs cyclic data structures in Rust, the existing theory of f

Haskell is the obvious answer. Rust is the bastard child of Haskell and C (my two loves). If one needs cyclic data structures in Rust, the existing theory of functional data structures is a great model for how to solve such problems. Persistent and reference-count-friendly data structures are brothers from different mothers. Haskell enforces pure functionality. Then one can relax and use Rust, and its arcane features will actually come as a relief.