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ASF GitHub Bot commented on FLINK-1159: --------------------------------------- Github user StephanEwen commented on a diff in the pull request: https://github.com/apache/flink/pull/1704#discussion_r58244518 --- Diff: flink-scala/src/main/scala/org/apache/flink/api/scala/extensions/impl/acceptPartialFunctions/OnDataSet.scala --- @@ -0,0 +1,111 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.flink.api.scala.extensions.impl.acceptPartialFunctions + +import org.apache.flink.api.common.typeinfo.TypeInformation +import org.apache.flink.api.scala.{DataSet, GroupedDataSet} + +import scala.reflect.ClassTag + +/** + * Wraps a data set, allowing to use anonymous partial functions to + * perform extraction of items in a tuple, case class instance or collection + * + * @param ds The wrapped data set + * @tparam T The type of the data set items, for which the type information must be known + */ +class OnDataSet[T: TypeInformation](ds: DataSet[T]) { --- End diff -- I think you do not need the `TypeInformation` context bound here. Functions should never need the implicit type info for the input (that is contained in the DataSet already), only ever for the return type. > Case style anonymous functions not supported by Scala API > --------------------------------------------------------- > > Key: FLINK-1159 > URL: https://issues.apache.org/jira/browse/FLINK-1159 > Project: Flink > Issue Type: Bug > Components: Scala API > Reporter: Till Rohrmann > Assignee: Stefano Baghino > > In Scala it is very common to define anonymous functions of the following form > {code} > { > case foo: Bar => foobar(foo) > case _ => throw new RuntimeException() > } > {code} > These case style anonymous functions are not supported yet by the Scala API. > Thus, one has to write redundant code to name the function parameter. > What works is the following pattern, but it is not intuitive for someone > coming from Scala: > {code} > dataset.map{ > _ match{ > case foo:Bar => ... > } > } > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)