Github user jaceklaskowski commented on a diff in the pull request:
https://github.com/apache/spark/pull/706#discussion_r12508408
--- Diff: project/SparkBuild.scala ---
@@ -297,7 +273,7 @@ object SparkBuild extends Build {
val chillVersion = "0.3.6"
val codahaleMetricsVersion = "3.0.0"
val jblasVersion = "1.2.3"
- val jets3tVersion = if
("^2\\.[3-9]+".r.findFirstIn(hadoopVersion).isDefined) "0.9.0" else "0.7.1"
+ val jets3tVersion =
"^2\\.[3-9]+".r.findFirstIn(hadoopVersion).fold("0.7.1")(_ => "0.9.0")
--- End diff --
I myself learnt it not so long ago and noticed it spurred some discussions
about it in the Scala community (with [Martin Ordersky
himself](http://stackoverflow.com/a/5332657/1305344)).
[Functional Programming in Scala](http://www.manning.com/bjarnason/) reads
on page 69 (in the pdf version):
*"Itâs fine to use pattern matching, though you should be able to
implement all the functions besides map and getOrElse without resorting to
pattern matching."*
So I followed the advice and applied Option.map(...).getOrElse(...) quite
intensively, but...IntelliJ IDEA just before I committed the change suggested
to replace it with fold. I thought I'd need to change my habits once more and
sent the PR.
With all that said, it's not clear what's the most idiomatic approach, but
[pattern matching is in my opinion a step back from
map/getOrElse](https://github.com/scala/scala/blob/2.12.x/src/library/scala/Option.scala#L156)
and there's no need for it.
I'd appreciate being corrected and could even replace `Option.fold` with
`map`/`getOrElse` if that would make the PR better for more committers.
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