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diff --git a/extra/boolean-expr/boolean-expr.factor b/extra/boolean-expr/boolean-expr.factor
index b2083eed5558edf375f8f7bc6c42dccb9c415e9c..5bf4bf3ad3594ae0a6f87882aac6e131c40015b6 100644 (file)
--- a/extra/boolean-expr/boolean-expr.factor
+++ b/extra/boolean-expr/boolean-expr.factor
@@ -11,8 +11,7 @@ TUPLE: ⋀ x y ;
 TUPLE: ⋁ x y ;
 TUPLE: ¬ x ;
 
-SINGLETON: ⊤
-SINGLETON: ⊥
+SINGLETONS: ⊤ ⊥ ;
 
 SINGLETONS: P Q R S T U V W X Y Z ;