: EXISTS? ( <name> -- flag , true if defined )
bl word find
- swap drop
+ nip 0<>
+; immediate
+
+: [DEFINED] ( <name> -- flag , true if defined, ANS )
+ bl word find
+ nip 0<>
+; immediate
+
+: [UNDEFINED] ( <name> -- flag , true if not defined, ANS )
+ bl word find
+ nip 0=
; immediate