H0n

H0n is a fictional programming language used in speculative fiction and teaching materials to explore language design, concurrency, and type systems. In the in-universe canon, H0n is designed to be approachable for learners while providing a realistic framework for experiments in purity, determinism, and safe concurrency.

H0n features static typing, algebraic data types, and pattern matching, with a focus on deterministic evaluation and explicit control of side effects through a lightweight effect system. The syntax is indentation-based and draws on influences from functional languages such as Haskell and ML, with pragmatic extensions for modularity and interoperability. Programs compile to a low-level intermediate form and can target platforms such as WebAssembly.

An example, in the fictional syntax, might define a simple recursive function to sum a list: let rec sum xs = match xs with | [] -> 0 | (x::xs') -> x + sum xs'. This example illustrates pattern matching and recursion common in the H0n design, not exact real-world syntax.

In its fictional universe, H0n serves as a vehicle for discussing trade-offs between purity and practicality, and for contrasting eager versus lazy evaluation strategies. It has minimal standard libraries, with a focus on core language concepts, and an ecosystem described as evolving through collaborative fan works and academic papers within the story world.

Notes: H0n is not an actual programming language, but a construct used in fiction and pedagogy to provoke discussion about language design. It is sometimes used as an example in curricula about type systems, concurrency, and compiler architecture.