improve error handling.

CXX/yapi.cpp

@@ -626,3 +626,14 @@ YAPQuery *YAPEngine::query( char *s ) {
   YAPQuery *n = new YAPQuery( s );
   return n;
 }
+
+YAPQuery *YAPEngine::safeQuery( char *s ) {
+  try 
+    {
+      YAPQuery *n = new YAPQuery( s );
+      return n;
+    }
+  catch (...) {
+    return 0;
+  }
+}

CXX/yapi.hh

@@ -576,6 +576,8 @@ public:
   void run( char *s) { __android_log_print(ANDROID_LOG_INFO, __FUNCTION__, "bef calling disp %s %p",s, _callback);  if (_callback) _callback->run(s); }
   /// build a query on the engine
   YAPQuery *query( char *s );
+  /// build a query on the engine
+  YAPQuery *safeQuery( char *s );
 };
 
 /*