Year: 2025
Type: conference-paper
Abstract: Invariants are an essential aspect to take into account for the correct implementation of data structures and their operations. This paper explores how to encode and enforce invariants at type level in Haskell, using Binary Search Trees (BSTs) and AVL trees as case studies. This means the encoding of invariants at type level using advanced features of Haskell type system and their later verification by the type checker. We compare three approaches for the type-level encoding of invariants: fully externalist, externalist, and internalist, each offering a different balance between modularity, safety, and complexity. We also show how to systematically extract standard implementations from correct, invariant-based code.
Authors: Nicolas Rodriguez, Alberto Pardo, Marcos Viera
Institution: Universidad de la República de Uruguay
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: gold
OpenAlex ID: W4415002393