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# Error: $interval:badprom
Non-$interval promise

    `$interval.cancel()` called with a promise that was not generated by `$interval()`.

## Description

This error occurs when calling $interval.cancel() with a promise that was not generated by the $interval service. This can, for example, happen when calling then()/catch() on the returned promise, which creates a new promise, and pass that new promise to $interval.cancel().

Example of incorrect usage that leads to this error:

    var promise = $interval(doSomething, 1000, 5).then(doSomethingElse);
    $interval.cancel(promise);

To fix the example above, keep a reference to the promise returned by $interval() and pass that to $interval.cancel():

    var promise = $interval(doSomething, 1000, 5);
    var newPromise = promise.then(doSomethingElse);
    $interval.cancel(promise);