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I guess things you've mentioned are widespread inside the Java community. But let's consider the things that have more global impact to compiler writers. For example, Scala LMS is a very interesting and promising recent project. Take a look at its source code -- no Visitor pattern inside. Visitor pattern may be necessary part of "Java culture", but for Scala I see no real reason to keep using it.

P.S. Thanks for the real perfomance data!

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Not quite a part of "Java culture". See Roslyn compiler, .NET Expression tree, C++ `std::visit` or tons of DOM tree rewriting js stuff.

Actually `visitor` and `pattern matching` are not mutually exclusive. imo the only difference is that in the visitor pattern, if you don't have anything to update, you just return the original node.

Thank you! I agree that just using of pattern matching may be not enough. But, instead of Visitor Pattern, I would use generic traversal "strategies" (combinators). My ideal is a DSL with first-class term rewriting rules + user definable strategies which take these rules as arguments. In fact, I already use such DSL for compiler writing :)

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