Document and rename internal option of modules.

1 files changed, 17 insertions, 17 deletions

diff --git a/lib/modules.nix b/lib/modules.nix
index a3c3fe7fc1ae..dcede0c46c63 100644
--- a/lib/modules.nix
+++ b/lib/modules.nix
@@ -17,51 +17,51 @@ rec {
      evalModules) and the less declarative the module set is. */
   evalModules = { modules
                 , prefix ? []
-                , # !!! This can be specified modularly now, can we remove it?
+                , # This would be remove in the future, Prefer _module.args option instead.
                   args ? {}
-                , # !!! This can be specified modularly now, can we remove it?
+                , # This would be remove in the future, Prefer _module.check option instead.
                   check ? true
                 }:
     let
+      # This internal module declare internal options under the `_module'
+      # attribute.  These options are fragile, as they are used by the
+      # module system to change the interpretation of modules.
       internalModule = rec {
         _file = ./modules.nix;
 
         key = _file;
 
         options = {
-          __internal.args = mkOption {
-            description = "Arguments passed to each module.";
-
-            # !!! Should this be types.uniq types.unspecified?
+          _module.args = mkOption {
             type = types.attrsOf types.unspecified;
-
             internal = true;
+            description = "Arguments passed to each module.";
           };
 
-          __internal.check = mkOption {
-            description = "Whether to check whether all option definitions have matching declarations.";
-
+          _module.check = mkOption {
             type = types.uniq types.bool;
-
             internal = true;
-
             default = check;
+            description = "Whether to check whether all option definitions have matching declarations.";
           };
         };
 
         config = {
-          __internal.args = args;
+          _module.args = args;
         };
       };
+
       closed = closeModules (modules ++ [ internalModule ]) { inherit config options; lib = import ./.; };
+
       # Note: the list of modules is reversed to maintain backward
       # compatibility with the old module system.  Not sure if this is
       # the most sensible policy.
       options = mergeModules prefix (reverseList closed);
+
       # Traverse options and extract the option values into the final
       # config set.  At the same time, check whether all option
       # definitions have matching declarations.
-      # !!! __internal.check's value can't depend on any other config values
+      # !!! _module.check's value can't depend on any other config values
       # without an infinite recursion. One way around this is to make the
       # 'config' passed around to the modules be unconditionally unchecked,
       # and only do the check in 'result'.
@@ -71,7 +71,7 @@ rec {
           if isOption v then v.value
           else yieldConfig (prefix ++ [n]) v) set) ["_definedNames"];
         in
-        if options.__internal.check.value && set ? _definedNames then
+        if options._module.check.value && set ? _definedNames then
           fold (m: res:
             fold (name: res:
               if set ? ${name} then res else throw "The option `${showOption (prefix ++ [name])}' defined in `${m.file}' does not exist.")
@@ -122,7 +122,7 @@ rec {
     let
       # Module arguments are resolved in a strict manner when attribute set
       # deconstruction is used.  As the arguments are now defined with the
-      # config.__interanl.args option, the strictness used on the attribute
+      # config._module.args option, the strictness used on the attribute
       # set argument would cause an infinite loop, if the result of the
       # option is given as argument.
       #
@@ -135,7 +135,7 @@ rec {
       requiredArgs = builtins.attrNames (builtins.functionArgs f);
       extraArgs = builtins.listToAttrs (map (name: {
         inherit name;
-        value = config.__internal.args.${name};
+        value = config._module.args.${name};
       }) requiredArgs);
     in f (extraArgs // arg)
   else