Index: libcfa/prelude/builtins.c
===================================================================
--- libcfa/prelude/builtins.c	(revision 1e6ea4e1482e7977552208c8d2dba74f5f58fed6)
+++ libcfa/prelude/builtins.c	(revision 0d8266c4f61d8230654336163621c6833a342f89)
@@ -10,6 +10,6 @@
 // Created On       : Fri Jul 21 16:21:03 2017
 // Last Modified By : Peter A. Buhr
-// Last Modified On : Tue Mar 26 23:10:36 2019
-// Update Count     : 95
+// Last Modified On : Tue Jun 25 18:06:52 2019
+// Update Count     : 97
 //
 
@@ -49,5 +49,5 @@
 void abort( const char fmt[], ... ) __attribute__ (( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ ));
 
-// increment/decrement unification
+// implicit increment, decrement if += defined, and implicit not if != defined
 
 static inline {
@@ -63,4 +63,7 @@
 	forall( dtype DT | sized(DT) | { void ?{}( DT &, DT ); void ^?{}( DT & ); DT & ?-=?( DT &, one_t ); } )
 	DT & ?--( DT & x ) { DT tmp = x; x -= 1; return tmp; }
+
+	forall( dtype DT | { int ?!=?( const DT &, zero_t ); } )
+	int !?( const DT & x ) { return !( x != 0 ); }
 } // distribution