encapsulation

[Tom Pledger]

Mark Fielder writes:
 | How does Haskell provide encapsulation?  What mechanisms does it
 | use?

The ways that spring to mind are modules and nested declarations:

    http://haskell.cs.yale.edu/onlinereport/modules.html
    http://haskell.cs.yale.edu/onlinereport/decls.html#sect4.4

 | What are Haskell's encapsulation strengths and weaknesses?

That's a matter of opinion.  It's strong in all the areas I care
about, but someone else may find it a pain that there's no way to
prevent a module from exporting all its evidence declarations.

 | Thanks for the help!
 | Mark