Why it is possible to build custom language for JVM, like Groovy, Scala, Clojure, Kotlin? -


these languages differ java in significant ways, oo system, type system (most notable).

the actual question whether jvm keeps track of objects under hood? there object inside jvm? responsibility of creators of such languages may interoperate java world, or achieved "by default"?

all jvm languages compile "java byte code". actually, jvm not have idea of programming language java. jvm spec specifies "class file", must fulfill rules. long provide compliant class files, created compiler e.g., code run on jvm. that's kotlin example.


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