clac: add missing expression body; thanks @joachifm for the catch

pkgs/tools/misc/clac/default.nix

@@ -0,0 +1,30 @@
+{stdenv, fetchFromGitHub}:
+stdenv.mkDerivation rec {
+  name = "${pname}-${version}";
+  pname = "clac";
+  version = "0.0.0.20170416";
+
+  src = fetchFromGitHub {
+    owner = "soveran";
+    repo = "clac";
+    rev = "828600b01e80166bc435d4d73506f0c3e16f2459";
+    sha256 = "08fhhvjrc7rn5fjjdqlallr76m6ybj3wm5gx407jbgfbky0fj7mb";
+  };
+
+  buildInputs = [];
+  makeFlags = ["PREFIX=$(out)"];
+
+  postInstall = ''
+    mkdir -p "$out/share/doc/${pname}"
+    cp README* LICENSE "$out/share/doc/${pname}"
+  '';
+
+  meta = {
+    inherit version;
+    description = "Interactive stack-based calculator";
+    license = stdenv.lib.licenses.bsd2;
+    maintainers = [stdenv.lib.maintainers.raskin];
+    platforms = stdenv.lib.platforms.linux;
+    homepage = "https://github.com/soveran/clac";
+  };
+}