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# Error: error:undef
Undefined Value

    Provider '{0}' must return a value from $get factory method.

## Description

This error results from registering a factory which does not return a value (or whose return value is undefined).

The following is an example of a factory which will throw this error upon injection:

    angular.module("badModule", []).
    factory("badFactory", function() {
      doLotsOfThings();
      butDontReturnAValue();
    });

In order to prevent the error, return a value of some sort, such as an object which exposes an API for working with the injected object.

    angular.module("goodModule", []).
    factory("goodFactory", function() {
      doLotsOfThings();
      butDontReturnAValue();

      return {
          doTheThing: function methodThatDoesAThing() {
          }
      };
    });