How comfortable are you with functional programming, and concurrent programming? I ask because my experience (and as always, YMMV) was that in languages that h

How comfortable are you with functional programming, and concurrent programming? I ask because my experience (and as always, YMMV) was that in languages that had 'familiar' syntax, new paradigms and concepts were a lot harder to pick up. I tried to learn functional programming in Scala, but it didn't take; I could still write things in a Java like way, which was what I was accustomed to, and it took a lot of extra effort to try and write them idiomatically. As a for instance, one of the most confusing (and thus, unused) structures in Erlang is the if structure. Why? Because it looks like something every developer already understands, while behaving in a completely different manner. That tinge of familiarity is a detriment for it.