[plt-scheme] help on how to write a frequency-counting function in a more functional way

On Wed, Apr 29, 2009 at 5:53 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> With our implementation, immutable hash tables are probably only better
> when they give you a better algorithm --- one that can needs O(1)
> operations on a mapping and where the operations are aren't
> "single-threaded" in the cumulative sense (i.e., you start with some
> mapping and you want to extend it in different, independent ways).

By the way, is for/hash implemented using a mutable hash table during
the loop?  Or is the constant factor slowdown not high enough to
bother?

--dougorleans at gmail.com