move global error configuration and status variables inside a class * error.h, error.cc (error_system): New class. (Vbacktrace_on_warning, Vbeep_on_error, Vdebug_on_caught, Vdebug_on_error, Vdebug_on_warning, Vlast_error_id, Vlast_error_message, Vlast_error_stack, Vlast_warning_id, Vlast_warning_message, Vquiet_warning, Vverbose_warning, buffer_error_messages, discard_error_messages, discard_warning_messages, in_try_catch, warning_options): Move global and file-scope static variables inside error_system class. Change all uses. * interpreter.h, interpreter.cc (m_error_system): New member variable. (get_error_system): New function. * interpreter-private.h, interpreter-private.cc (__get_error_system__): New function.

--- a/libinterp/corefcn/interpreter-private.h	Fri Jun 07 13:29:41 2019 -0400
+++ b/libinterp/corefcn/interpreter-private.h	Fri May 31 15:49:38 2019 +0000
@@ -37,6 +37,7 @@
   class cdef_manager;
   class child_list;
   class dynamic_loader;
+  class error_system;
   class gtk_manager;
   class help_system;
   class history_system;
@@ -52,6 +53,8 @@
 
   extern dynamic_loader& __get_dynamic_loader__ (const std::string& who);
 
+  extern error_system& __get_error_system__ (const std::string& who);
+
   extern help_system& __get_help_system__ (const std::string& who);
 
   extern history_system& __get_history_system__ (const std::string& who);