anchor.diff:            # pkgs: config: {..}
             cfg2 = cfg {} {};
           in
  -        if __isFunction cfg0 then
  -          if builtins.isAttrs cfg1 then cfg1
  +        if builtins.isFunction cfg0 then
  +          if isAttrs cfg1 then cfg1
             else builtins.trace "Use '{pkgs, config, ...}:'." cfg2
           else cfg0;
   
  
positive.code:   # - notHandle is a function which takes the list of values are not handle
    # by this function.
    handleOptionSets = optionHandler@{export, notHandle, ...}: path: opts:
      if all __isAttrs opts then
        lib.zip (attr: opts:
          let
            # Compute the path to reach the attribute.
  
negative.code:   # Otherwise, the property is kept on all sub-attribute definitions.
    onOverrideDelay = name: p@{property, content, ...}:
      let inherit (property) template; in
      if isAttrs template && template != {} then
        if hasAttr name template then
          p // {
            property = p.property // {
              template = builtins.getAttr name template;
  