change output references from attrset to lambda

this is so that we can distinguish a ref from a literal parameter that
might be a attrset

examples/router-with-l2tp.nix

@@ -30,6 +30,7 @@
   lns = { hostname = "l2tp.aaisp.net.uk"; address = "194.4.172.12"; };
 
   inherit (pkgs.liminix.services) oneshot longrun target;
+  inherit (pkgs.liminix) outputRef;
   inherit (pkgs.pseudofile) dir symlink;
   inherit (pkgs) serviceFns;
   svc = config.system.service;
@@ -99,14 +100,18 @@ in rec {
         localDomain = "lan";
       };
     };
-    wan = {
+    wan =
-      interface = let
+      let
-        secret = path: { service = config.services.secrets; inherit path; };
+        secret = outputRef config.services.secrets;
+        username = secret "ppp/username";
+        password = secret "ppp/password";
+      in {
+        interface =
+          let
             pppoe = svc.pppoe.build {
               interface = config.hardware.networkInterfaces.wan;
               debug = true;
-          username = secret "ppp/username";
+              inherit username password;
-          password = secret "ppp/password";
             };
 
             l2tp =
@@ -123,11 +128,7 @@ in rec {
                 };
                 l2tpd= svc.l2tp.build {
                   lns = lns.address;
-              ppp-options = [
+                  inherit username password;
-                "debug" "+ipv6" "noauth"
-                "name" rsecrets.l2tp.name
-                "password" rsecrets.l2tp.password
-              ];
                   dependencies = [config.services.lns-address route check-address];
                 };
               in
@@ -154,10 +155,7 @@ in rec {
         channel = "6";
         ieee80211n = 1;
       } // wirelessConfig // {
-        wpa_passphrase = {
+        wpa_passphrase = outputRef config.services.secrets "wpa_passphrase";
-          service = config.services.secrets;
-          path = "wpa_passphrase";
-        };
       };
 
       "${rsecrets.ssid}5" = rec {
@@ -170,14 +168,10 @@ in rec {
         ieee80211n = 1;
         ieee80211ac = 1;
       } // wirelessConfig // {
-        wpa_passphrase = {
+        wpa_passphrase = outputRef config.services.secrets "wpa_passphrase";
-          service = config.services.secrets;
-          path = "wpa_passphrase";
       };
     };
   };
-  };
-
 
   services.bootstrap-dhcpc = svc.network.dhcp.client.build {
     interface = config.services.wwan;

modules/hostapd/service.nix

@@ -30,7 +30,7 @@ let
   literal_or_output = o: ({
     string = builtins.toJSON;
     int = builtins.toJSON;
-    set = (o: "output(${builtins.toJSON o.service}, ${builtins.toJSON o.path})");
+    lambda = (o: "output(${builtins.toJSON (o "service")}, ${builtins.toJSON (o "path")})");
   }.${builtins.typeOf o}) o;
 
   conf =

modules/ppp/default.nix

@@ -40,12 +40,12 @@ in {
         description = "ethernet interface to run PPPoE over";
       };
       username = mkOption {
-        type = types.nullOr liminix.lib.types.replacable;
+        type = types.nullOr (liminix.lib.types.replacable types.str);
         default = null;
         description = "username";
       };
       password = mkOption {
-        type = types.nullOr liminix.lib.types.replacable;
+        type = types.nullOr (liminix.lib.types.replacable types.str);
         default = null;
         description = "password";
       };
@@ -83,12 +83,12 @@ in {
         description = "hostname or address of the L2TP network server";
       };
       username = mkOption {
-        type = types.nullOr liminix.lib.types.replacable;
+        type = types.nullOr (liminix.lib.types.replacable types.str);
         default = null;
         description = "username";
       };
       password = mkOption {
-        type = types.nullOr liminix.lib.types.replacable;
+        type = types.nullOr (liminix.lib.types.replacable types.str);
         default = null;
         description = "password";
       };
@@ -116,6 +116,7 @@ in {
       };
       ppp-options = mkOption {
         type = types.listOf types.str;
+        default = [];
         description = "options supplied on ppp command line";
       };
     };

modules/ppp/l2tp.nix

@@ -44,7 +44,7 @@ let
     let v = o: ({
           string = builtins.toJSON;
           int = builtins.toJSON;
-          set = (o: "output(${builtins.toJSON o.service}, ${builtins.toJSON o.path})");
+          lambda = (o: "output(${builtins.toJSON (o "service")}, ${builtins.toJSON (o "path")})");
         }.${builtins.typeOf o}) o;
     in  o: "{{ ${v o} }}";
 

modules/ppp/pppoe.nix

@@ -44,7 +44,7 @@ let
     let v = o: ({
           string = builtins.toJSON;
           int = builtins.toJSON;
-          set = (o: "output(${builtins.toJSON o.service}, ${builtins.toJSON o.path})");
+          lambda = (o: "output(${builtins.toJSON (o "service")}, ${builtins.toJSON (o "path")})");
         }.${builtins.typeOf o}) o;
     in  o: "{{ ${v o} }}";
   ppp-options' =

pkgs/default.nix

@@ -14,6 +14,9 @@ in {
       uimage = callPackage ./kernel/uimage.nix { };
       kernel = callPackage ./kernel { };
     };
+    outputRef = service : path :
+      let h = { inherit service path; };
+      in x : h.${x};
     callService = path : parameters :
       let pkg = callPackage path {};
           checkTypes = t : p : typeChecked (builtins.toString path) t p;
@@ -43,18 +46,10 @@ in {
             description = "parametrisable s6-rc service definition";
             check = x: lib.isAttrs x && x ? parameters && x ? build;
           };
-          replacable = types.either
+          replacable = t : types.either
-            types.str
+            t
-            (types.submodule {
+            # function might return a service or a path
-              options = {
+            (types.functionTo types.anything);
-                service = mkOption {
-                  type = service;
-                };
-                path = mkOption {
-                  type = types.str;
-                };
-              };
-            });
         };
       inherit typeChecked;
     };