diff --git a/src/_impl/_archimedean_spiral_impl.scad b/src/_impl/_archimedean_spiral_impl.scad
index fabfb6f8..36c2cad7 100644
--- a/src/_impl/_archimedean_spiral_impl.scad
+++ b/src/_impl/_archimedean_spiral_impl.scad
@@ -1,9 +1,9 @@
 function _radian_step(b, theta, l) =
     let(
-        r_square = pow(b * theta, 2),
+        r_square = (b * theta) ^ 2,
         double_r_square = 2 * r_square
     )
-    acos((double_r_square - pow(l, 2)) / double_r_square) / 180 * PI;
+    acos((double_r_square - l ^ 2) / double_r_square) / 180 * PI;
 
 function _find_radians(b, point_distance, radians, n, count = 1) =
     let(pre_radians = radians[count - 1])
@@ -21,5 +21,5 @@ function _archimedean_spiral_impl(arm_distance, init_angle, point_distance, num_
     [
         for(theta = _find_radians(b, point_distance, [init_radian], num_of_points)) 
            let(r = b * theta, a = (rt_dir == "CT_CLK" ? 1 : -1) * theta * 57.2958)
-           [[r * cos(a), r * sin(a)], a]
+           [r * [cos(a), sin(a)], a]
     ];
\ No newline at end of file
diff --git a/src/_impl/_bezier_curve_impl.scad b/src/_impl/_bezier_curve_impl.scad
index 7a690fb1..25c2ed3c 100644
--- a/src/_impl/_bezier_curve_impl.scad
+++ b/src/_impl/_bezier_curve_impl.scad
@@ -7,7 +7,7 @@ function _combi(n, k) =
             [1,3,3,1]   // n = 3: for Cubic Bézier curves
         ]  
     )
-    n < len(bi_coef) ? bi_coef[n][k] : (
+    n < 4 ? bi_coef[n][k] : (
         k == 0 ? 1 : (_combi(n, k - 1) * (n - k + 1) / k)
     );
         
@@ -21,12 +21,12 @@ function _bezier_curve_point2(t, points) =
     [
         bezier_curve_coordinate(
             t, 
-            [for(p = points) p[0]], 
+            [for(p = points) p.x], 
             n
         ),
         bezier_curve_coordinate(
             t,  
-            [for(p = points) p[1]], 
+            [for(p = points) p.y], 
             n
         )
     ];
@@ -36,17 +36,17 @@ function _bezier_curve_point3(t, points) =
     [
         bezier_curve_coordinate(
             t, 
-            [for(p = points) p[0]], 
+            [for(p = points) p.x], 
             n
         ),
         bezier_curve_coordinate(
             t,  
-            [for(p = points) p[1]], 
+            [for(p = points) p.y], 
             n
         ),
         bezier_curve_coordinate(
             t, 
-            [for(p = points) p[2]], 
+            [for(p = points) p.z], 
             n
         )
     ];
diff --git a/src/_impl/_contours_impl.scad b/src/_impl/_contours_impl.scad
index 84eb0c95..820ee936 100644
--- a/src/_impl/_contours_impl.scad
+++ b/src/_impl/_contours_impl.scad
@@ -21,7 +21,7 @@ function interpolated_pt(p0, p1, threshold) =
 function _isolines_pn_label(pts, threshold) =
     [
         for(row = pts)
-        [for(p = row) [p.x, p.y, p.z, p.z >= threshold]]
+        [for(p = row) [each p, p.z >= threshold]]
     ]; 
     
 function _isolines_corner_value(cell_pts) =
@@ -116,10 +116,7 @@ function _isolines_of(cell_pts, threshold) =
 function _marching_squares_isolines(points, threshold) = 
     let(labeled_pts = _isolines_pn_label(points, threshold))
     [
-        for(
-            y = [0:len(labeled_pts) - 2], 
-            x = [0:len(labeled_pts[0]) - 2]
-        )            
+        for(y = [0:len(labeled_pts) - 2], x = [0:len(labeled_pts[0]) - 2])            
             let(
                 p0 = labeled_pts[y][x],
                 p1 = labeled_pts[y + 1][x],
@@ -145,11 +142,12 @@ function _isobands_tri_label(pts, lower, upper) =
         for(row = pts)
         [
             for(p = row) 
-            let(label = 
-                p[2] < lower ? "0" : 
-                p[2] >= lower && p[2] <= upper ? "1" : "2"
+            let(
+                z = p.z,
+                label = z < lower ? "0" : 
+                        z >= lower && z <= upper ? "1" : "2"
             )
-            [p[0], p[1], p[2], label]
+            [each p, label]
         ]
     ]; 
     
@@ -1393,10 +1391,7 @@ function _isobands_of(cell_pts, lower, upper) =
 function _marching_squares_isobands(points, lower, upper) = 
     let(labeled_pts = _isobands_tri_label(points, lower, upper))
     [
-        for(
-            y = [0:len(labeled_pts) - 2], 
-            x = [0:len(labeled_pts[0]) - 2]
-        )
+        for(y = [0:len(labeled_pts) - 2], x = [0:len(labeled_pts[0]) - 2])
             let(
                 p0 = labeled_pts[y][x],
                 p1 = labeled_pts[y + 1][x],