I don't believe the Scala compiler understands the difference between your two examples the same way that you do. Looking at a few similar cases, I've only found the bytecode produced to be the same regardless of which style is used.
On Wed, Apr 13, 2016 at 7:46 PM, Hyukjin Kwon <gurwls...@gmail.com> wrote: > Hi all, > > I recently noticed that actually there are some usages of functional > transformations (eg. map, foreach and etc.) with extra anonymous closure. > > For example, > > ...map(item => { > ... > }) > > which can be just simply as below: > > ...map { item => > ... > } > > I wrote a regex to find all of them and corrected them for a PR (I did not > submit yet). > > However, I feel a bit hesitating because only reasons I can think for this > are, > > firstly, Spark coding guides in both > https://github.com/databricks/scala-style-guide and > https://cwiki.apache.org/confluence/display/SPARK/Spark+Code+Style+Guide > are not using the examples as above > > secondly, I feel like extra anonymous closure can harm performance but > I am too sure, > > which I think are not persuasive enough. > > > > To cut it short, my questions are, > > 1. Would this be a proper change for a PR? > > 2. Would there be more explicit reasons to remove extra closure not only > for coding style? > > > Thanks! >