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Predicate debug_print_hook/3
 prolog:debug_print_hook(+Topic, +Format, +Args) is semidet[multifile, library(syslog)]
Integration of debug/3 with the syslog facility. If syslog is enabled, debug/3 is re-routed to use the syslog facilities. If the topic of the debug message matches one of the sylog priority values (see syslog/2), the message is sent with the corresponding syslog priority. Otherwise it it sent with the debug priority.
 prolog:debug_print_hook(+Topic, +Format, +Args) is semidet[multifile, library(debug)]
Hook called by debug/3. This hook is used by the graphical frontend that can be activated using prolog_ide/1:
?- prolog_ide(debug_monitor).