Hmmm, this message never made it to popt-devel.
I'm attempting a Bloom filter implementation in popt now, will likely
also
attempt choosing 1-of-N exclusively as described here:
http://rpm5.org/community/popt-devel/0112.html
and perhaps finish up "option groups" for feature parity with
getopt_long()
(but perhaps not, option groups would be very annoying to do correctly).
So last chance to voice an opinion ...
73 de Jeff
Begin forwarded message:
From: Jeff Johnson <[email protected]>
Date: July 10, 2009 11:24:46 AM EDT
To: [email protected]
Subject: Adding option bit sets using Bloom filters?
One of the problems that I frequently encounter in RPM using
POPT is the tedium of keeping track of bits and names and
options and functionality, i.e. all the bleeping baggage.
The usual problem that I have in RPM is that I end up running out of
bits.
One solution would be to use a Bloom filter for a open-ended class
of options
that map to bits. One Bloom filter would be needed to establish
whether an option is in the permitted set, another Bloom filter would
be needed to return values that were explicitly mentioned.
The nice thing about Bloom filters is that they partition all
possible option strings without the tedium of committing to
an explicit mapping onto bits.
I'd likely do the implementation slightly differently than
most option processing, marking a subtable (which carries the strings
necessary to initialize the permitted option Bloom filter) in
this field in struct poptOption:
/*...@observer@*/ /*...@null@*/
const char * longName;
and returning which (possibly multiple) options were seen (as always
in popt) in
/*...@shared@*/ /*...@null@*/
void * arg; /*!< depends on argInfo */
with the {m,k} parameters used for the Bloom filter overloaded into
char shortName; /*!< may be NUL */
int val; /*!< 0 means don't return, just update
flag */
For more on Bloom filters, see
http://en.wikipedia.org/wiki/Bloom_filters
I already have an implementation in RPM that could be moved
to POPT, the implementation is quite straight-forward.
Opinions? I'll likely proceed with an implementation the
next time I get to popt hacking.
73 de Jeff
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