add slice

test/util/test_slice.scad

@@ -0,0 +1,15 @@
+module test_slice() {
+    echo("==== test_slice ====");
+
+    include <unittest.scad>;
+    include <util/slice.scad>;
+
+    lt = [for(c = "helloworld") c];
+    expected1 = [for(c = "hello") c];
+    expected2 = [for(c = "world") c];
+
+    assert(expected1 == slice(lt, 0, 5)); 
+    assert(expected2 == slice(lt, 5)); 
+}
+
+test_slice();