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backend/node_modules/mnemonist/utils/comparators.js

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+/**
+ * Mnemonist Heap Comparators
+ * ===========================
+ *
+ * Default comparators & functions dealing with comparators reversing etc.
+ */
+var DEFAULT_COMPARATOR = function(a, b) {
+  if (a < b)
+    return -1;
+  if (a > b)
+    return 1;
+
+  return 0;
+};
+
+var DEFAULT_REVERSE_COMPARATOR = function(a, b) {
+  if (a < b)
+    return 1;
+  if (a > b)
+    return -1;
+
+  return 0;
+};
+
+/**
+ * Function used to reverse a comparator.
+ */
+function reverseComparator(comparator) {
+  return function(a, b) {
+    return comparator(b, a);
+  };
+}
+
+/**
+ * Function returning a tuple comparator.
+ */
+function createTupleComparator(size) {
+  if (size === 2) {
+    return function(a, b) {
+      if (a[0] < b[0])
+        return -1;
+
+      if (a[0] > b[0])
+        return 1;
+
+      if (a[1] < b[1])
+        return -1;
+
+      if (a[1] > b[1])
+        return 1;
+
+      return 0;
+    };
+  }
+
+  return function(a, b) {
+    var i = 0;
+
+    while (i < size) {
+      if (a[i] < b[i])
+        return -1;
+
+      if (a[i] > b[i])
+        return 1;
+
+      i++;
+    }
+
+    return 0;
+  };
+}
+
+/**
+ * Exporting.
+ */
+exports.DEFAULT_COMPARATOR = DEFAULT_COMPARATOR;
+exports.DEFAULT_REVERSE_COMPARATOR = DEFAULT_REVERSE_COMPARATOR;
+exports.reverseComparator = reverseComparator;
+exports.createTupleComparator = createTupleComparator;