policy.nix

let

  pkgs = import <nixpkgs> {};

  pname = a: (builtins.parseDrvName pkgs."${a}".name).name;

  versionParts = a:
    builtins.splitVersion (builtins.parseDrvName pkgs."${a}".name).version;

  separator = "_";

  path = n : v:
    if v == []
    then n
    else "${n}${separator}${builtins.concatStringsSep "_" v}";

  versions = versionParts:
   if builtins.length versionParts == 0
   then [[]]
   else
     [[]] ++
      (builtins.map
        (rest: [(builtins.elemAt versionParts 0)] ++ rest)
         (versions (builtins.tail versionParts)));

  validPaths = a:
    builtins.concatStringsSep " or "
      (builtins.map
        (vs: path (pname a) vs)
        (versions (versionParts a)));

  policy = a: "${a} | ${validPaths a} ";

  attrpaths = [
    #"qt56"
    "autoconf213"
    "automake111x"
    "libgit2_0_25"
    "apacheKafka_0_10"
    "dbus-sharp-glib-2_0"
    "antlr3_5"
    "bison3"
    "automoc4"
    "fplll_20160331"
    "owncloud-client"
    "libavc1394"
    "icu58"
    ];

in
{
  result =
    builtins.concatStringsSep "\n" (builtins.map policy attrpaths)
      + "\n";
}

run.sh

nix eval --raw -f policy.nix result