Re: [Chicken-users] hash-tables

[Felix Winkelmann]

Am Sun, 23 Nov 2003 14:19:11 +0100 hat address@hidden 
<address@hidden> geschrieben:

> A couple of questions about hash-tables:
>
> 1) Should I use hash-tables or associative lists if performance is 
> important? How do they
>     compare?

For short data-sets an association-list will likely be more efficient.
Since Chicken uses a copying garbage-collector, one cannot (unfortunately)
just take the address of an object in the heap and use that as a hash-code
(which would be damn fast), so the hash-code has to be computed from
the contents of the data. Actually, I exclusively use a-lists, unless
I know it's going to be a big table. Doing some benchmarking for your
particular application might be worthwhile.

> 2) I see in the manual that "get" and "put!" can have a "property" 
> argument; what's that?

The property may be anything, but it will be compared using `eq?'.
(yes, that should be documented... ;-)


cheers,
felix