After 10 years of JVM development, I've done nearly 2 years in Erlang now. It's a very different experience. I've learned and used several other languages to varying degrees over the past few years including Lisp, Prolog, Io, Ruby, Scala, Groovy, and Clojure. I think Lisp is awesome and hope to begin using Lisp Flavored Erlang soon.
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