add bsearch

test/util/test_bsearch.scad

@@ -0,0 +1,19 @@
+use <util/sort.scad>;
+use <util/bsearch.scad>;
+
+module test_bsearch() {
+    echo("==== test_bsearch ====");
+
+    points = [[1, 1], [3, 4], [7, 2], [5, 2]];
+    sorted = sort(points, by = "vt"); //  [[1, 1], [5, 2], [7, 2], [3, 4]]
+
+    assert(bsearch(sorted, [7, 2]) == 2);
+
+    xIs5 = function(elem) elem[0] - 5;
+    assert(bsearch(sorted, xIs5) == 1);
+
+    yIs4 = function(elem) elem[1] - 4;
+    assert(bsearch(sorted, yIs4) == 3);
+}
+
+test_bsearch();