Array (and string) slicing should now be in master for Genie Please test and let me know if there are any problems with it
jamie On Sat, 2010-05-22 at 19:56 -0400, Arc Riley wrote: > We are working with IO which returns the number of bytes written, not > utf-8 characters. > > The following shows this fairly well: > init > var utf8 = "𐑣𐑩𐑤𐑴, 𐑢𐑻𐑤𐑛!" > print "%d", (int) utf8.length > 11 > > Python (3.1.2) does the same: > >>> utf8 = "𐑣𐑩𐑤𐑴, 𐑢𐑻𐑤𐑛!" > >>> len(utf8) > 11 > > However, we can see that this is not the number of bytes: > >>> buff = bytes(utf8, "utf-8") > >>> len(buff) > 35 > > Of course we can't do this with Genie since it has a broken to_utf8() > function: > print "%d", (int) utf8.to_utf8().length > 4196432 > > IO read/write functions return bytes for the number read and written. > For this reason, I wrote us up an alternative mapping of GString for > using chra[] instead of string, and we avoid string whenever we have > data which could have utf8 content. > > The pointer solution seems to work in this case, but Genie does not > have slice support currently (I checked), where Vala does and > implements it in nearly the same way Python does. > > > > > On Sat, May 22, 2010 at 11:46 AM, jamie <jamie.mccr...@googlemail.com> > wrote: > > On Sat, 2010-05-22 at 06:38 -0400, Arc Riley wrote: > > I'm migrating some C code to Genie and ran into a troubling > limitation; the > > following line of code does not seem to have an equivalent > in Genie: > > > > session->wbuff = g_string_append_len(session->wbuff, > str+sent, > > len-sent); > > > > What this means is "when you can't send all the data you'd > like, append the > > rest to our (known to be empty) GString buffer". > > > > The key part here is "the rest" - getting a slice of an > array, such as C's > > array + value syntax (Incompatible operand) or Python's > array[start:] syntax > > (error: syntax error, expected `]' but got `:' with previous > identifier). > > > > We can't use Genie strings for the buffer because UTF8 > length != byte > > length. > > > _______________________________________________ > > You should be using the StringBuilder class for this > > public unowned StringBuilder append_len (string val, ssize_t > len); > > (StringBuilder is a GString) > > Also string class has a size method which uses strlen - it > would > probably be clearer if it was called ByteLength > > See http://git.gnome.org/browse/vala/tree/vapi/glib-2.0.vapi > > If there are still problems let me know - I will be bug fixing > genie > tomorrow > > jamie > > > _______________________________________________ vala-list mailing list vala-list@gnome.org http://mail.gnome.org/mailman/listinfo/vala-list
