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Greg Hogan commented on FLINK-3333: ----------------------------------- I can think of four return values from a user defined {{reduce()}}: left, right, new object, or a long-lived local object. The long-lived user object can be later modified by the user, but storing and later modifying the left or right input objects is unsafe. That is what I consider an edge case, an action that no user is expected to perform, and that cannot be prevented without impacting performance (a.k.a. disabling object reuse). > Documentation about object reuse should be improved > --------------------------------------------------- > > Key: FLINK-3333 > URL: https://issues.apache.org/jira/browse/FLINK-3333 > Project: Flink > Issue Type: Bug > Components: Documentation > Affects Versions: 1.0.0 > Reporter: Gabor Gevay > Assignee: Gabor Gevay > Priority: Blocker > Fix For: 1.0.0 > > > The documentation about object reuse \[1\] has several problems, see \[2\]. > \[1\] > https://ci.apache.org/projects/flink/flink-docs-master/apis/batch/index.html#object-reuse-behavior > \[2\] > https://docs.google.com/document/d/1cgkuttvmj4jUonG7E2RdFVjKlfQDm_hE6gvFcgAfzXg/edit -- This message was sent by Atlassian JIRA (v6.3.4#6332)