[plt-scheme] likely 3.99.0.22 -> 3.99.0.23 incompatibility: hash tables

Matthew Flatt wrote:
> While we're cleaning up the language in v4, we'd like to do something
> about the API for using hash tables:

<snip description>

I don't have any particular problem with this; I have had need for
side-effect free tables before but used galore.plt from PLaneT instead.
 However if you don't want to use "table" the noun (which, again, I have
no quarrel) one could use "map" (could be confusing) or "relation" (less
confusing, more verbose, also subtly wrong, as relations are more like A
-> P(B) than A -> B).

Graham