gsignal: add a clarification to the docs

As evidenced by a mistake that I made recently, this documentation could
use a little bit of clarification.
This commit is contained in:
Ryan Lortie 2014-11-28 16:20:40 -05:00
parent d511d6b37f
commit c476f7cd26

View File

@ -2867,6 +2867,12 @@ g_signal_handlers_disconnect_matched (gpointer instance,
* Returns whether there are any handlers connected to @instance for the
* given signal id and detail.
*
* If @detail is 0 then it will only match handlers that were connected
* without detail. If @detail is non-zero then it will match handlers
* connected both without detail and with the given detail. This is
* consistent with how a signal emitted with @detail would be delivered
* to those handlers.
*
* One example of when you might use this is when the arguments to the
* signal are difficult to compute. A class implementor may opt to not
* emit the signal if no one is attached anyway, thus saving the cost