···1+{ stdenv, fetchgit, ocaml, findlib, menhir, which }:
2+3+let inherit (stdenv.lib) getVersion versionAtLeast; in
4+5+assert versionAtLeast (getVersion ocaml) "3.12";
6+7+stdenv.mkDerivation {
8+9+ name = "eff-20140928";
10+11+ src = fetchgit {
12+ url = "https://github.com/matijapretnar/eff.git";
13+ rev = "90f884a790fddddb51d4d1d3b7c2edf1e8aabb64";
14+ sha256 = "28e389b35e6959072c245c2e79fe305885b1b2d44ff540a02a097e09e9f9698f";
15+ };
16+17+ buildInputs = [ ocaml findlib menhir which ];
18+19+ doCheck = true;
20+ checkTarget = "test";
21+22+ meta = with stdenv.lib; {
23+ homepage = "http://www.eff-lang.org";
24+ description = "A functional programming language based on algebraic effects and their handlers";
25+ longDescription = ''
26+ Eff is a functional language with handlers of not only exceptions,
27+ but also of other computational effects such as state or I/O. With
28+ handlers, you can simply implement transactions, redirections,
29+ backtracking, multi-threading, and much more...
30+ '';
31+ license = licenses.bsd2;
32+ platforms = ocaml.meta.platforms;
33+ maintainers = [ maintainers.jirkamarsik ];
34+ };
35+}