[Haskell-cafe] implementing python-style dictionary in Haskell

[Luke Palmer]

On Tue, Nov 18, 2008 at 10:37 AM, David Menendez <dave at zednenem.com> wrote:
> This isn't really a fair comparison. Map, IntMap, and Trie are
> persistent data structures, and Python dictionaries are ephemeral.
> (That is, when you "add" a key to a Map, you actually create a new one
> that shares structure with the old one, and both can be used in
> subsequent code. In Python, you would have to copy the dictionary.)

But when these persistent data structures are used in a
single-threaded way, why should we not hope for the performance to be
comparable?

It may not be easy, but just saying "they are persistent" is not
really an excuse.

Luke