use Metrics::Any::Adapter 'Stderr';
This Metrics::Any adapter type writes observations of metric values to the standard error stream. This may be helpful while debugging or otherwise testing code that reports metrics.
For example, by setting the "METRICS_ANY_ADAPTER" environment variable to configure the adapter, a metric log will be written to the terminal as a side-effect of running a unit test:
$ METRICS_ANY_ADAPTER=Stderr perl -Mblib t/01test.t
This adapter type does not support batch mode reporting.