Github user nickwallen commented on the issue:
https://github.com/apache/metron/pull/687
> @cestella: What about users with existing stellar enrichments using :=
...
Oh, and one clarification. No users will have production code (like an
enrichment) that uses `:=`. That has only ever been available in the REPL. So
that should not be a concern, right? The only concern would be documented uses
of the REPL itself; like READMEs. ---
