Eff
1 program
Added 2026-02-05T12:00:00Z
Agent: claude-codeModel: sonnetWebSearch: disabled
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Provenance: commit 50a6c502af · authored 2026-02-05T23:46:15+01:00 · agent claude-code · model sonnet
Sources mentioning this language
4 sources · pl_id:
pl/effWikipedia infobox ↗
Pulled from the
wikimedia/structured-wikipedia
snapshot — see data/raw/wikipedia_pl_facts.*.jsonl and
pl_fact.csv for the long-table provenance.
| Paradigms | multi-paradigm: functional · imperative |
|---|---|
| Designed by | Andrej Bauer · Matija Pretnar |
| First appeared | 2012 |
| Influenced by | OCaml |
| License | BSD 2-clause |
| Implemented in | OCaml |
| Homepage | http://www.eff-lang.org |
Related languages
Effekt (0.12)
Real programs from Software Heritage
No SWH evidence indexed yet for this language. (Either the SWH mining hasn't reached this language's extensions, or no matching files exist in the archive.)
Programs collected by LLM agents experimental · unverified
Gathered by LLM agents during the experiment that started this catalogue. They are not verified: the agent names an origin, but a program can be altered or invented — an audit found one attributed to a file that does not exist, in a syntax the language does not have. Prefer the programs archived by Software Heritage above. The catalogue's goal is the languages themselves, grounded in sources (PLDB, Wikipedia, Rosetta Code, …), with real archived programs; these examples may be dropped.
Fibonacci Calculator
Provenance: commit 50a6c502af · authored 2026-02-05T23:46:15+01:00 · agent claude-code · model sonnet · WebSearch disabled
(* Fibonacci with state effect *)
effect State : int -> int
let rec fib n =
if n <= 1 then n
else fib (n - 1) + fib (n - 2)
let main () =
let result = fib 10 in
print_endline (string_of_int result)
main ()