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A portion of the configuration tree which is elided from `config`.

     

       
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#### `_type` {#module-system-lib-evalModules-return-value-_type}

     

       
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A nominal type marker, always `"configuration"`.

     

       
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#### `configurationClass` {#module-system-lib-evalModules-return-value-_configurationClass}

     

       
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Equal to the [`class` parameter](#module-system-lib-evalModules-param-class).

     

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              within a configuration, but can be used in module imports.

     

       
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            '';

     

       
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          };

     

       
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          _module.class = mkOption {

     

       
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            readOnly = true;

     

       
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            internal = true;

     

       
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            description = lib.mdDoc ''

     

       
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              If the `class` attribute is set and non-`null`, the module system will reject `imports` with a different `class`.

     

       
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              This option contains the expected `class` attribute of the current module evaluation.

     

       
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            '';

     

       
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          };

     

       
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        };

     

       
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        config = {

     
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            inherit extendModules;

     

       
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            moduleType = type;

     

       
239
       
 
       
          };

     

       
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-
       
          _module.class = class;

     

       
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          _module.specialArgs = specialArgs;

     

       
242
       
 
       
        };

     

       
243
       
 
       
      };

     
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        config = checked (removeAttrs config [ "_module" ]);

     

       
338
       
 
       
        _module = checked (config._module);

     

       
339
       
 
       
        inherit extendModules type;

     

       
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340
       
 
       
      };

     

       
341
       
 
       
    in result;

     

       
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              within a configuration, but can be used in module imports.

     

       
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            '';

     

       
222
       
 
       
          };

     

       
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        };

     

       
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225
       
 
       
        config = {

     
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            inherit extendModules;

     

       
228
       
 
       
            moduleType = type;

     

       
229
       
 
       
          };

     

       
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230
       
 
       
          _module.specialArgs = specialArgs;

     

       
231
       
 
       
        };

     

       
232
       
 
       
      };

     
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326
       
 
       
        config = checked (removeAttrs config [ "_module" ]);

     

       
327
       
 
       
        _module = checked (config._module);

     

       
328
       
 
       
        inherit extendModules type;

     

       
329
       
+
       
        configurationClass = class;

     

       
330
       
 
       
      };

     

       
331
       
 
       
    in result;

     

       
332
       
 
       


     

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365
       
 
       
# Class checks, evalModules

     

       
366
       
 
       
checkConfigOutput '^{ }$' config.ok.config ./class-check.nix

     

       
0
       
 
       

     

       
367
       
 
       
checkConfigError 'The module .*/module-class-is-darwin.nix was imported into nixos instead of darwin.' config.fail.config ./class-check.nix

     

       
368
       
 
       
checkConfigError 'The module foo.nix#darwinModules.default was imported into nixos instead of darwin.' config.fail-anon.config ./class-check.nix

     

       
369
       
 
       


     

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365
       
 
       
# Class checks, evalModules

     

       
366
       
 
       
checkConfigOutput '^{ }$' config.ok.config ./class-check.nix

     

       
367
       
+
       
checkConfigOutput '"nixos"' config.ok.configurationClass ./class-check.nix

     

       
368
       
 
       
checkConfigError 'The module .*/module-class-is-darwin.nix was imported into nixos instead of darwin.' config.fail.config ./class-check.nix

     

       
369
       
 
       
checkConfigError 'The module foo.nix#darwinModules.default was imported into nixos instead of darwin.' config.fail-anon.config ./class-check.nix

     

       
370