My experiance differs. For instance, I spent a few days picking through OCaml a while back. I can't say I'm proficient in the langauge, but I did learn a lot about modern type systems (C and Java are not modern type systems). I'm sure I could pick up other things if I used the language every day for a few years, but even the little I did learn was valuable.
"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.
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