Github user crafty-coder commented on a diff in the pull request: https://github.com/apache/spark/pull/22031#discussion_r208387111 --- Diff: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/higherOrderFunctions.scala --- @@ -442,3 +442,93 @@ case class ArrayAggregate( override def prettyName: String = "aggregate" } + +/** + * Transform elements in an array using the transform function. This is similar to + * a `map` in functional programming. + */ +// scalastyle:off line.size.limit +@ExpressionDescription( + usage = "_FUNC_(expr, func) - Merges the two given arrays, element-wise, into a single array using function. If one array is shorter, nulls are appended at the end to match the length of the longer array, before applying function.", + examples = """ + Examples: + > SELECT _FUNC_(array(1, 2, 3), x -> x + 1); --- End diff -- The examples are not accurate. You could something like: ``` > SELECT _FUNC_(array(1, 2, 3), array('a', 'b', 'c'), (x, y) -> (y, x)); array(('a', 1), ('b', 3), ('c', 5)) > SELECT _FUNC_(array(1, 2), array(3, 4), (x, y) -> x + y)); array(4, 6) > SELECT _FUNC_(array('a', 'b', 'c'), array('d', 'e', 'f'), (x, y) -> concat(x, y)); array('ad', 'be', 'cf') ```
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