So true. I've been a professional developer for 15 years and I've worked with several languages (C++/Java/PHP/Python/Perl/C#/Ruby/JS/Groovy), but man, does this whole "functional" stuff is being hard to get a hold of. Specially Scala, for me, is very hard to understand the syntax, even after a year of working with Play. The most frustrating part is understanding the flow of the data in chained calls like in map-reduce.