Does Haskell support object oriented programming

Question

Does it support concepts like separation of declaration and implementation (interfaces and classes in Java)?

How about restricting access (like access modifiers in J

Answer 1

Type classes are indeed the only constructs that remind remotely on OO concepts - in this case, on interfaces. Though, unlike in java, type classes are not types.

One good thing about type classes is that I can make totally unrelated, already existing types members of a type class. Whereas in java, sometimes one thinks: These classes A from package org.a and B from com.b that I am using ought really be implementing interface Y from a third package, but there is no way to do it that would not require a lot of boilerplate code, additional indirections, marshalling etc.

BTW, as an elderly programmer I'd like to note that "separation of declaration and implementation" has per se nothing to do with OOP. Just because most OO-langugaes support it does not mean the concept was not well known for a long time before OO was invented. Interested youngsters who think that programming before mainstreaming of OO must have been on a "stone age" level may look up MODULA, for example, where separation of declaration and implementation is not only possible, but enforced by the language.