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# Error: ng:areq
Bad Argument

    Argument '{0}' is {1}

## Description

AngularJS often asserts that certain values will be present and truthy using a helper function. If the assertion fails, this error is thrown. To fix this problem, make sure that the value the assertion expects is defined and matches the type mentioned in the error.

If the type is `undefined`, make sure any newly added controllers/directives/services are properly defined and included in the script(s) loaded by your page.