fennel: extract some common functions into a shareable module

examples/acquire-delegated-prefix.fnl

@@ -1,12 +1,5 @@
 (local inotify (require :inotify))
-
-(fn merge [table1 table2]
-  (collect [k v (pairs table2) &into table1]
-    k v))
-
-(fn split [sep string]
-  (icollect [v (string.gmatch string (.. "([^" sep "]+)"))]
-    v))
+(local { : merge : split : file-exists? : system } (require :anoia))
 
 (fn parse-prefix [str]
   (fn parse-extra [s]
@@ -24,12 +17,6 @@
 ;;(parse-prefix "2001:8b0:de3a:40dc::/64,7198,7198")
 ;;(parse-prefix "2001:8b0:de3a:1001::/64,7198,7188,excluded=1/2,thi=10")
 
-
-(fn file-exists? [name]
-  (match (io.open name :r)
-    f (do (f:close) true)
-    _ false))
-
 (fn read-line [name]
   (with-open [f (assert (io.open name :r) (.. "can't open file " name))]
     (f:read "*l")))
@@ -80,9 +67,6 @@
           (table.insert deleted (parse-prefix prefix))))
     (values added deleted)))
 
-;;(fn execute [s] (do (print s) true))
-(fn execute [s] (assert (os.execute s)))
-
 (let [[state-directory lan-device] arg
       dir (watch-directory state-directory)]
   (var prefixes [])
@@ -92,10 +76,10 @@
         (let [new-prefixes (split " " (dir:read-line "/prefixes"))
               (added deleted) (changes prefixes new-prefixes)]
           (each [_ p (ipairs added)]
-            (execute
+            (system
              (.. "ip address add " p.prefix "::1/" p.len " dev " lan-device)))
           (each [_ p (ipairs deleted)]
-            (execute
+            (system
              (.. "ip address del " p.prefix "::1/" p.len " dev " lan-device)))
     	  (set prefixes new-prefixes)))
     (dir:wait-events)))

examples/acquire-delegated-prefix.nix

@@ -1,7 +1,8 @@
 {
   writeFennelScript
 , linotify
+, anoia
 }:
 writeFennelScript "acquire-delegated-prefix"
-  [ linotify ]
+  [ linotify anoia ]
   ./acquire-delegated-prefix.fnl

pkgs/anoia/README

@@ -0,0 +1,14 @@
+
+In Terry Pratchett's Discworld novels, Anoi is a minor goddess of Things That Stick In Drawers
+
+> Often, but not uniquely, a ladle, but sometimes a metal spatula or,
+> rarely, a mechanical egg-whisk that nobody in the house admits to
+> ever buying. The desperate mad rattling and cries of ‘How can it
+> close on the damn thing but not open with it? Who bought this? Do we
+> ever use it?’ is as praise unto Anoia. She also eats corkscrews.
+
+This is a library of miscellaneous Fennel code used in Liminix that is
+shared between various scripts but doesn't really fit together. It is
+not a public stable interface - while any Liminix code is welcome to
+use it, it's suject to reshuffle, rearrangement, refactor or rejection
+without notice.

pkgs/anoia/default.nix

@@ -0,0 +1,19 @@
+{
+  fennel
+, stdenv
+, lua
+}:
+let pname =  "anoia";
+in stdenv.mkDerivation {
+  inherit pname;
+  version = "0.1";
+  src = ./.;
+  nativeBuildInputs = [ fennel ];
+  buildPhase = ''
+    fennel --compile init.fnl > init.lua
+  '';
+  installPhase = ''
+    mkdir -p "$out/share/lua/${lua.luaversion}/${pname}"
+    cp *.lua "$out/share/lua/${lua.luaversion}/${pname}"
+  '';
+}

pkgs/anoia/init.fnl

@@ -0,0 +1,16 @@
+(fn merge [table1 table2]
+  (collect [k v (pairs table2) &into table1]
+    k v))
+
+(fn split [sep string]
+  (icollect [v (string.gmatch string (.. "([^" sep "]+)"))]
+    v))
+
+(fn file-exists? [name]
+  (match (io.open name :r)
+    f (do (f:close) true)
+    _ false))
+
+(fn system [s] (assert (os.execute s)))
+
+{ : merge : split : file-exists? : system }

pkgs/default.nix

@@ -58,4 +58,5 @@
   odhcp-script = callPackage ./odhcp-script {};
   fennel = callPackage ./fennel {};
   fennelrepl = callPackage ./fennelrepl {};
+  anoia = callPackage ./anoia {};
 }

pkgs/write-fennel-script/default.nix

@@ -6,7 +6,11 @@
 }:
 name : packages : source :
   let
-    luapath = builtins.map (f: "${f}/share/lua/${lua.luaversion}/?.lua;") packages;
+    luapath = builtins.map
+      (f:
+        "${f}/share/lua/${lua.luaversion}/?.lua;" +
+        "${f}/share/lua/${lua.luaversion}/?/init.lua;")
+      packages;
     luacpath = builtins.map (f: "${f}/lib/lua/${lua.luaversion}/?.so;") packages;
   in stdenv.mkDerivation {
     inherit name;