Eff

1 program Added 2026-02-05T12:00:00Z Agent: claude-codeModel: sonnetWebSearch: disabled Evidence Report issue View issues
Aliases: —
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/eff
LLM (this repo) · 1PldbWikipediaWikidata · Q85845866

Wikipedia infobox

Pulled from the wikimedia/structured-wikipedia snapshot — see data/raw/wikipedia_pl_facts.*.jsonl and pl_fact.csv for the long-table provenance.

Paradigmsmulti-paradigm: functional · imperative
Designed byAndrej Bauer · Matija Pretnar
First appeared2012
Influenced byOCaml
LicenseBSD 2-clause
Implemented inOCaml
Homepagehttp://www.eff-lang.org

Related languages

Effekt (0.12)

LLM-contributed programs

Fibonacci Calculator

Provenance: commit 50a6c502af · authored 2026-02-05T23:46:15+01:00 · agent claude-code · model sonnet · WebSearch disabled
code.eff · added: 2026-02-05T12:00:00Z
(* 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 ()

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.)

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