Why UDF can not be non-static inner class ?

[Jeff Zhang]

The reason I ask this is that I try to use UDF in flink scala shell, but I will hit the following error.

After some investigation, I found it is a scala issue. https://issues.scala-lang.org/browse/SI-2034

The workaround is to add argument ""-Yrepl-class-based" for scala shell. 

But then I hit another error in 

https://github.com/apache/flink/blob/master/flink-libraries/flink-table/src/main/scala/org/apache/flink/table/functions/utils/UserDefinedFunctionUtils.scala#L63

After I remove the code above, I can make everything work,  so I just wonder why UDF can not be non-static inner class ? 

 

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