Github user twalthr commented on a diff in the pull request: https://github.com/apache/flink/pull/5015#discussion_r151406114 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/expressions/ExpressionParser.scala --- @@ -141,6 +142,7 @@ object ExpressionParser extends JavaTokenParsers with PackratParsers { lazy val dataType: PackratParser[TypeInformation[_]] = PRIMITIVE_ARRAY ~ "(" ~> dataType <~ ")" ^^ { ct => Types.PRIMITIVE_ARRAY(ct) } | OBJECT_ARRAY ~ "(" ~> dataType <~ ")" ^^ { ct => Types.OBJECT_ARRAY(ct) } | + MAP ~ "(" ~> dataType ~ dataType <~ ")" ^^ { tt => Types.MAP(tt._1, tt._2)} | --- End diff -- Maybe you can test an identity cast just to test the functionality.
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