erlang: use makeOverridable for customizations

pkgs/development/beam-modules/lib.nix

···
 
 rec {
 
-  /* Uses generic-builder to evaluate provided drv containing OTP-version specific data.
+  /* Similar to callPackageWith/callPackage, but without makeOverridable
+  */
+  callPackageWith = autoArgs: fn: args:
+    let
+      f = if builtins.isFunction fn then fn else import fn;
+      auto = builtins.intersectAttrs (builtins.functionArgs f) autoArgs;
+    in f (auto // args);
+
+  callPackage = callPackageWith pkgs;
+
+  /* Uses generic-builder to evaluate provided drv containing OTP-version
+  specific data.
 
   drv: package containing version-specific args;
   builder: generic builder for all Erlang versions;
-  gargs: arguments passed to the generic-builder, used mostly to customize dependencies;
-  args: arguments merged into version-specific args, used mostly to enable/disable high-level OTP
-    features, like ODBC or WX support;
+  args: arguments merged into version-specific args, used mostly to customize
+        dependencies;
 
-  Please note that "mkDerivation" defined here is the one called from R16.nix and similar files.
+  Arguments passed to the generic-builder are overridable, used to
+  enable/disable high-level OTP features, like ODBC or WX support;
+
+  Please note that "mkDerivation" defined here is the one called from R16.nix
+  and similar files.
   */
-  callErlang = drv: gargs: args: pkgs.callPackage drv (
-    let builder = pkgs.callPackage ../../development/interpreters/erlang/generic-builder.nix gargs;
-    in {
-      mkDerivation = a: builder (a // args);
-    });
+  callErlang = drv: args:
+    let
+      builder = callPackage ../../development/interpreters/erlang/generic-builder.nix args;
+    in
+      callPackage drv {
+        mkDerivation = pkgs.makeOverridable builder;
+      };
 
 }

pkgs/top-level/beam-packages.nix

···
     erlang_odbc_javac = erlangR18_odbc_javac;
 
     # These are standard Erlang versions, using the generic builder.
-    erlangR16 = lib.callErlang ../development/interpreters/erlang/R16.nix {} {};
-    erlangR16_odbc = lib.callErlang ../development/interpreters/erlang/R16.nix {} {
-      odbcSupport = true;
-    };
-    erlangR17 = lib.callErlang ../development/interpreters/erlang/R17.nix {} {};
-    erlangR17_odbc = lib.callErlang ../development/interpreters/erlang/R17.nix {} {
-      odbcSupport = true;
-    };
-    erlangR17_javac = lib.callErlang ../development/interpreters/erlang/R17.nix {} {
-      javacSupport = true;
-    };
-    erlangR17_odbc_javac = lib.callErlang ../development/interpreters/erlang/R17.nix {} {
+    erlangR16 = lib.callErlang ../development/interpreters/erlang/R16.nix {};
+    erlangR16_odbc = erlangR16.override { odbcSupport = true; };
+    erlangR17 = lib.callErlang ../development/interpreters/erlang/R17.nix {};
+    erlangR17_odbc = erlangR17.override { odbcSupport = true; };
+    erlangR17_javac = erlangR17.override { javacSupport = true; };
+    erlangR17_odbc_javac = erlangR17.override {
       javacSupport = true; odbcSupport = true;
     };
     erlangR18 = lib.callErlang ../development/interpreters/erlang/R18.nix {
       wxGTK = wxGTK30;
-    } {};
-    erlangR18_odbc = lib.callErlang ../development/interpreters/erlang/R18.nix {
-      wxGTK = wxGTK30;
-    } {
-      odbcSupport = true;
     };
-    erlangR18_javac = lib.callErlang ../development/interpreters/erlang/R18.nix {
-      wxGTK = wxGTK30;
-    } {
-      javacSupport = true;
-    };
-    erlangR18_odbc_javac = lib.callErlang ../development/interpreters/erlang/R18.nix {
-      wxGTK = wxGTK30;
-    } {
+    erlangR18_odbc = erlangR18.override { odbcSupport = true; };
+    erlangR18_javac = erlangR18.override { javacSupport = true; };
+    erlangR18_odbc_javac = erlangR18.override {
       javacSupport = true; odbcSupport = true;
     };
     erlangR19 = lib.callErlang ../development/interpreters/erlang/R19.nix {
       wxGTK = wxGTK30;
-    } {};
-    erlangR19_odbc = lib.callErlang ../development/interpreters/erlang/R19.nix {
-      wxGTK = wxGTK30;
-    } {
-      odbcSupport = true;
-    };
-    erlangR19_javac = lib.callErlang ../development/interpreters/erlang/R19.nix {
-      wxGTK = wxGTK30;
-    } {
-      javacSupport = true;
     };
-    erlangR19_odbc_javac = lib.callErlang ../development/interpreters/erlang/R19.nix {
-      wxGTK = wxGTK30;
-    } {
+    erlangR19_odbc = erlangR19.override { odbcSupport = true; };
+    erlangR19_javac = erlangR19.override { javacSupport = true; };
+    erlangR19_odbc_javac = erlangR19.override {
       javacSupport = true; odbcSupport = true;
     };