On Wed, Jun 25, 2008 at 11:47:39AM -0700, David E. Wheeler wrote: > * There seem to still be some implicit CASTS to text that I'd like to > duplicate. For example, select '192.168.1.2'::cidr::text;` works, but > `select '192.168.1.2'::cidr::citext;` does not. Where can I find the C > functions that do these casts for TEXT so that I can put them to work > for citext, too? The internal cast functions used in the old citext > distribution don't exist at all on 8.3.
Hmm, casts to/from text are somewhat "magic" in postgres. They are implemented by calling the usual type input/output function. I have no idea how to extend that to other types. > * There are casts from text that I'd also like to harness for use by > citext, like `cidr(text)`. Where can I find these C functions as well? > (The upshot of this and the previous points is that I'd like citext to > be as compatible with TEXT as possible, and I just need to figure out > how to fill in the gaps in that compatibility.) As above, they're probably not as seperate functions but a special hack inthe casting code. > * Regular expression and LIKE comparisons using the the operators > properly work case-insensitively, but functions like replace() and > regexp_replace() do not. Should they? and if so, how can I make them > do so? Regexes have case-insensetive modifiers, don't they? In which case I don't think it'd be becessary. > * As for my C programming, well, what's broken? I'm especially > concerned that I pfree variables appropriately, but I'm not at all > clear on what needs to be freed. Martijn mentioned before that btree > comparison functions free memory, but I'm such a C n00b that I don't > know what that actually means for my implementation. I'd actually > appreciate a bit of pedantry here. :-) When creating an index, your comparison functions are going ot be called O(N log N) times. If they leak into a context that isn't regularly freed you may have a problem. I'd suggest loking at how the text comparisons do it. PG_FREE_IF_COPY() is probably a good idea because the incoming tuples may be detoasted. > * Am I in fact getting an appropriate nul-terminated string in my > cilower() function using this code? > > char * str = DatumGetCString( > DirectFunctionCall1( textout, PointerGetDatum( arg ) ) > ); Yes. Have a nice day, -- Martijn van Oosterhout <[EMAIL PROTECTED]> http://svana.org/kleptog/ > Please line up in a tree and maintain the heap invariant while > boarding. Thank you for flying nlogn airlines.
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