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Stephan Ewen commented on FLINK-952: ------------------------------------ It would be nice to get around that, which is quite a piece of work though. > TypeExtractor requires the argument types of the UDF to be identical to the > parameter types > ------------------------------------------------------------------------------------------- > > Key: FLINK-952 > URL: https://issues.apache.org/jira/browse/FLINK-952 > Project: Flink > Issue Type: Bug > Reporter: Till Rohrmann > Assignee: Till Rohrmann > > The TypeExtractor checks for each operation whether the DataSet element types > are valid arguments for the UDF. However, it checks for strict equality > instead of a subtype relationship. Thus the following computation would not > work even though it should semantically be correct. > DataSet[B].map(new MapFunction[A,A](){ A map(A x)}) with B being a sub class > of A. -- This message was sent by Atlassian JIRA (v6.2#6252)