Store parse actions' precedences as ranges, not sets

src/compiler/precedence_range.cc

@@ -0,0 +1,35 @@
+#include "compiler/precedence_range.h"
+
+namespace tree_sitter {
+
+PrecedenceRange::PrecedenceRange() : min(0), max(0), empty(true) {}
+
+PrecedenceRange::PrecedenceRange(int min, int max)
+    : min(min), max(max), empty(false) {}
+
+void PrecedenceRange::add(int new_value) {
+  if (empty) {
+    min = new_value;
+    max = new_value;
+    empty = false;
+  } else {
+    if (new_value < min)
+      min = new_value;
+    else if (new_value > max)
+      max = new_value;
+  }
+}
+
+bool PrecedenceRange::operator<(const PrecedenceRange &other) const {
+  if (empty)
+    return !other.empty;
+  else
+    return (min < other.min && max <= other.min) ||
+           (min == other.min && max < other.max);
+}
+
+bool PrecedenceRange::operator==(const PrecedenceRange &other) const {
+  return (empty == other.empty) && (min == other.min) && (max == other.max);
+}
+
+}  // namespace tree_sitter