anchor.diff:        fromOf = attrByPath (splitString "." from)
           (abort "Internal error: option `${from}' should be declared.");
       in
  -      [{
  -        options = setFrom (mkOption {
  -          description = "${status.name} of <option>${to}</option>.";
  -          apply = x: status.msg.use (toOf config);
  -          visible = false;
  -        });
  -      }] ++
  -      [{
  -        options = setTo (mkOption {
  -          extraConfigs =
  -            let externalDefs = (fromOf options).definitions; in
  -            if externalDefs == [] then []
  -            else map (def: def.value) (status.msg.define externalDefs);
  -        });
  -      }];
  +      [ { options = setFrom (mkOption {
  +            description = "${status.name} of <option>${to}</option>.";
  +            apply = x: status.msg.use (toOf config);
  +            visible = false;
  +          });
  +        }
  +        { options = setTo (mkOption {
  +            extraConfigs =
  +              let externalDefs = (fromOf options).definitions; in
  +              if externalDefs == [] then []
  +              else map (def: def.value) (status.msg.define externalDefs);
  +          });
  +        }
  +      ];
   
   in zipModules ([]
   
  
positive.code:       else head v
      ) list;
  
    rename = statusTemplate: from: to: with pkgs.lib;
      let
        status = statusTemplate from to;
        setTo = setAttrByPath (splitString "." to);
  
negative.code: { config, pkgs, options, ... }:
  
  with pkgs.lib;
  
  let
  
  