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> Where was pre-Java 1.5's generic HashMap?

In java.util.Hashtable as implementation of the java.util.Dictionary interface, since version 1.1 back in 1997.

Implemented using s/interface{}/Object/g with ability to use any type as key, as long as, hashCode() and equals () are overriden.

Also allows for fine tuning of the capacity and load factor.

> Or closures?

In anonymous inner classes. A pain to use when compared with real closures, but doable nonetheless.




That is not a generic HashMap. See masklinn's response.

The fact is, the comparison between Go and "pre generics Java" is a bad one. There are many substantial differences, and blessed parameterized types in Go is absolutely one of them.


In the discussion's context, "generic" is about parameterized types (type-safe collections), not about working on any object.


Which Go lacks and the OP was stating it has.


* Go has a generic hashmap, the builtin map type is one of the magical special-status generic collections (with arrays, slices and channels).

* pre-1.5 Java did not have one, its only parametric type was the low-level array


Ah, ok. That is correct.




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