On 14.04.2013 21:31, Jonas Kulla wrote:
2013/4/14 Alexander Krivács Schrøder <alexschrod gmail com <mailto:alexschrod gmail com>> Hi. I'm trying to use Glib.TimeVal with its from_iso8601() initializer, but I can't get the generated C code not to contain a call to g_get_current_time() first. At first, I tried this Vala code: string iso8601_date = "1999-05-31T11:20:00"; TimeVal time_val; time_val.from_iso8601(iso8601_date); but that makes the compiler complain: error: use of possibly unassigned local variable `time_val' So then I tried this code: string iso8601_date = "1999-05-31T11:20:00"; TimeVal time_val = TimeVal(); time_val.from_iso8601(iso8601_date); but that makes the compiler output the following code: g_get_current_time (&time_val); g_time_val_from_iso8601 (iso8601_date, &time_val); What do I do to make it not call g_get_current_time()? I know it's probably minimal, but it's still wasted CPU cycles and extraneous code to compile and whatnot, and I want the option to leave it out if at all possible. If it isn't possible, a way to make it possible should be considered to be implemented. Regards, Alexander K. Schrøder _______________________________________________ vala-list mailing list vala-list gnome org <mailto:vala-list gnome org> https://mail.gnome.org/mailman/listinfo/vala-list Hi, GTimeVal seems a little bit problematic. Ideally, you would want to declare the "from_iso8601" method as a named constructor to circumvent the default one (which results in the g_get_current_time), and from a small test I just did this works out fine Vala wise. The only problem I see is that this call returns a boolean indicating whether the conversion was successful, which would be lost without any way to find out the result. I guess the way it should really be done is to have the default constructor just initialize the struct to zero and have the "get_current_time" as a separate method, but for that additional glib code would have to exist. I think your best trade off would be to go with your first suggestion and ignore the valac warning. But why is circumventing the get_current_time call so important to you? Are you running this code in a tight loop? Jonas
I would go with my first suggestion, except it's an error and not a warning, so it doesn't compile at all. No, I don't particularly need to circumvent the call. This is mostly a theoretical desire to be able to accomplish in Vala the same thing I could accomplish in C. Were I to write the code in C, I could just leave out the call, so why shouldn't I be able to accomplish the same goal in Vala? Or, more appropriately, why should Vala HAVE to call g_get_current_time just for me to get a hold of a TimeVal struct? For the most part, Vala produces code about as efficient as manual C code can be written, which is one of the main reasons why I like Vala so much, but when it decides to force me to throw in a function call that I don't need, that feeling of efficiency falls a little short. So yeah... mostly intellectual curiosity, really. Regards, Alexander K. Schrøder
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