1 files changed, 32 insertions, 0 deletions

diff --git a/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java
new file mode 100644
index 00000000..84b4b771
--- /dev/null
+++ b/subprojects/store-query/src/main/java/tools/refinery/store/query/literal/CallPolarity.java
@@ -0,0 +1,32 @@
+package tools.refinery.store.query.literal;
+
+public enum CallPolarity {
+        POSITIVE(true, false),
+        NEGATIVE(false, false),
+        TRANSITIVE(true, true);
+
+        private final boolean positive;
+
+        private final boolean transitive;
+
+        CallPolarity(boolean positive, boolean transitive) {
+                this.positive = positive;
+                this.transitive = transitive;
+        }
+
+        public boolean isPositive() {
+                return positive;
+        }
+
+        public boolean isTransitive() {
+                return transitive;
+        }
+
+        public CallPolarity negate() {
+                return switch (this) {
+                        case POSITIVE -> NEGATIVE;
+                        case NEGATIVE -> POSITIVE;
+                        case TRANSITIVE -> throw new IllegalArgumentException("Transitive polarity cannot be negated");
+                };
+        }
+}