add Ox.nextValue

source/Ox/js/Array.js

@@ -568,6 +568,35 @@ Ox.makeArray = function(value) {
     return ret;
 };
 
+/*@
+Ox.nextValue <f> Next value, given an array of numbers, a number and a direction
+    (array, value, direction) -> <n> Next value
+    array <[n]> Sorted array of numbers
+    value <n> Number
+    direction <n|1> Direction (-1 for left or 1 for right)
+    > Ox.nextValue([0, 2, 4, 6, 8], 5, -1)
+    4
+    > Ox.nextValue([], 1, 1)
+    void 0
+@*/
+Ox.nextValue = function(array, value, direction) {
+    var found = false, nextValue;
+    direction = direction || 1;
+    direction == -1 && array.reverse();
+    Ox.forEach(array, function(v) {
+        if (direction == 1 ? v > value : v < value) {
+            nextValue = v;
+            found = true;
+            return false; // break
+        }
+    });
+    direction == -1 && array.reverse();
+    if (!found) {
+        nextValue = array[direction == 1 ? 0 : array.length - 1];
+    }
+    return nextValue;
+};
+
 /*@
 Ox.range <f> Python-style range
     (stop) -> <[n]> range