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# `Module Unavailable`
error in component `$injector`

    Module '{0}' is not available! You either misspelled the module name or forgot to load it. If registering a module ensure that you specify the dependencies as the second argument.

## Description

This error occurs when trying to "re-open" a module that has not yet been defined.

To define a new module, call `angular.module` with a name and an array of dependent modules, like so:

    // When defining a module with no module dependencies,
    // the requires array should be defined and empty.
    var myApp = angular.module('myApp', []);

To retrieve a reference to the same module for further configuration, call `angular.module` without the `requires` array.

    var myApp = angular.module('myApp');

Calling `angular.module` without the `requires` array when the module has not yet been defined causes this error to be thrown. To fix it, define your module with a name and an empty array, as in the first example above.