Revert "Merge remote-tracking branch 'upstream/master'"

This reverts commit fd2c073bb2, reversing
changes made to d4c7fab7ed.

arrays.scad

@@ -142,59 +142,18 @@ function last(list) =
     list[len(list)-1];
 
 
-// Function: list_head()
+// Function: delete_last()
 // Usage:
-//   list = list_head(list,<to>);
+//   list = delete_last(list);
 // Topics: List Handling
-// See Also: select(), slice(), list_tail(), last()
+// See Also: select(), slice(), subindex(), last()
 // Description:
-//   Returns the head of the given list, from the first item up until the `to` index, inclusive.
-//   If the `to` index is negative, then the length of the list is added to it, such that
-//   `-1` is the last list item.  `-2` is the second from last.  `-3` is third from last, etc.
-//   If the list is shorter than the given index, then the full list is returned.
-// Arguments:
-//   list = The list to get the head of.
-//   to = The last index to include.  If negative, adds the list length to it.  ie: -1 is the last list item.
-// Examples:
-//   hlist = list_head(["foo", "bar", "baz"]);  // Returns: ["foo", "bar"]
-//   hlist = list_head(["foo", "bar", "baz"], -3); // Returns: ["foo"]
-//   hlist = list_head(["foo", "bar", "baz"], 2);  // Returns: ["foo","bar"]
-//   hlist = list_head(["foo", "bar", "baz"], -5); // Returns: []
-//   hlist = list_head(["foo", "bar", "baz"], 5);  // Returns: ["foo","bar","baz"]
-function list_head(list, to=-2) =
+//   Returns a list with all but the last entry from the input list.  If input is empty, returns empty list.
+// Example:
+//   nlist = delete_last(["foo", "bar", "baz"]);  // Returns: ["foo", "bar"]
+function delete_last(list) =
    assert(is_list(list))
-   assert(is_finite(to))
-   to<0? [for (i=[0:1:len(list)+to]) list[i]] :
-   to<len(list)? [for (i=[0:1:to]) list[i]] :
-   list;
-
-
-// Function: list_tail()
-// Usage:
-//   list = list_tail(list,<from>);
-// Topics: List Handling
-// See Also: select(), slice(), list_tail(), last()
-// Description:
-//   Returns the tail of the given list, from the `from` index up until the end of the list, inclusive.
-//   If the `from` index is negative, then the length of the list is added to it, such that
-//   `-1` is the last list item.  `-2` is the second from last.  `-3` is third from last, etc.
-//   If you want it to return the last three items of the list, use `from=-3`.
-// Arguments:
-//   list = The list to get the tail of.
-//   from = The first index to include.  If negative, adds the list length to it.  ie: -1 is the last list item.
-// Examples:
-//   tlist = list_tail(["foo", "bar", "baz"]);  // Returns: ["bar", "baz"]
-//   tlist = list_tail(["foo", "bar", "baz"], -1); // Returns: ["baz"]
-//   tlist = list_tail(["foo", "bar", "baz"], 2);  // Returns: ["baz"]
-//   tlist = list_tail(["foo", "bar", "baz"], -5); // Returns: ["foo","bar","baz"]
-//   tlist = list_tail(["foo", "bar", "baz"], 5);  // Returns: []
-function list_tail(list, from=1) =
-   assert(is_list(list))
-   assert(is_finite(from))
-   from>=0? [for (i=[from:1:len(list)-1]) list[i]] :
-   let(from = from + len(list))
-   from>=0? [for (i=[from:1:len(list)-1]) list[i]] :
-   list;
+   list==[] ? [] : slice(list,0,-2);
 
 
 // Function: force_list()

beziers.scad

@@ -574,7 +574,7 @@ function bezier_line_intersection(curve, line) =
 //   p2 = [30, 30];
 //   trace_path([p0,p1,p2], showpts=true, size=0.5, color="green");
 //   fbez = fillet3pts(p0,p1,p2, 10);
-//   trace_bezier(select(fbez,1,-2), size=1);
+//   trace_bezier(slice(fbez, 1, -2), size=1);
 function fillet3pts(p0, p1, p2, r, d, maxerr=0.1, w=0.5, dw=0.25) = let(
         r = get_radius(r=r,d=d),
         v0 = unit(p0-p1),
@@ -942,7 +942,7 @@ module bezier_polygon(bezier, splinesteps=16, N=3) {
     assert(is_int(splinesteps));
     assert(len(bezier)%N == 1, str("A degree ",N," bezier path shound have a multiple of ",N," points in it, plus 1."));
     polypoints=bezier_path(bezier, splinesteps, N);
-    polygon(points=polypoints);
+    polygon(points=slice(polypoints, 0, -1));
 }
 
 

distributors.scad

@@ -294,9 +294,9 @@ module distribute(spacing=undef, sizes=undef, dir=RIGHT, l=undef)
     spc = !is_undef(l)? ((l - sum(gaps)) / ($children-1)) : default(spacing, 10);
     gaps2 = [for (gap = gaps) gap+spc];
     spos = dir * -sum(gaps2)/2;
-    spacings = cumsum([0, each gaps2]);
     for (i=[0:1:$children-1]) {
-        $pos = spos + spacings[i] * dir;
+        totspc = sum(concat([0], slice(gaps2, 0, i)));
+        $pos = spos + totspc * dir;
         $idx = i;
         translate($pos) children(i);
     }
@@ -339,9 +339,9 @@ module xdistribute(spacing=10, sizes=undef, l=undef)
     spc = !is_undef(l)? ((l - sum(gaps)) / ($children-1)) : default(spacing, 10);
     gaps2 = [for (gap = gaps) gap+spc];
     spos = dir * -sum(gaps2)/2;
-    spacings = cumsum([0, each gaps2]);
     for (i=[0:1:$children-1]) {
-        $pos = spos + spacings[i] * dir;
+        totspc = sum(concat([0], slice(gaps2, 0, i)));
+        $pos = spos + totspc * dir;
         $idx = i;
         translate($pos) children(i);
     }
@@ -384,9 +384,9 @@ module ydistribute(spacing=10, sizes=undef, l=undef)
     spc = !is_undef(l)? ((l - sum(gaps)) / ($children-1)) : default(spacing, 10);
     gaps2 = [for (gap = gaps) gap+spc];
     spos = dir * -sum(gaps2)/2;
-    spacings = cumsum([0, each gaps2]);
     for (i=[0:1:$children-1]) {
-        $pos = spos + spacings[i] * dir;
+        totspc = sum(concat([0], slice(gaps2, 0, i)));
+        $pos = spos + totspc * dir;
         $idx = i;
         translate($pos) children(i);
     }
@@ -429,9 +429,9 @@ module zdistribute(spacing=10, sizes=undef, l=undef)
     spc = !is_undef(l)? ((l - sum(gaps)) / ($children-1)) : default(spacing, 10);
     gaps2 = [for (gap = gaps) gap+spc];
     spos = dir * -sum(gaps2)/2;
-    spacings = cumsum([0, each gaps2]);
     for (i=[0:1:$children-1]) {
-        $pos = spos + spacings[i] * dir;
+        totspc = sum(concat([0], slice(gaps2, 0, i)));
+        $pos = spos + totspc * dir;
         $idx = i;
         translate($pos) children(i);
     }

math.scad

@@ -544,8 +544,9 @@ function _lcm(a,b) =
 
 // Computes lcm for a list of values
 function _lcmlist(a) =
-    len(a)==1 ? a[0] :
-    _lcmlist(concat(lcm(a[0],a[1]),list_tail(a,2)));
+    len(a)==1 
+    ?   a[0] 
+    :   _lcmlist(concat(slice(a,0,len(a)-2),[lcm(a[len(a)-2],a[len(a)-1])]));
 
 
 // Function: lcm()

paths.scad

@@ -878,14 +878,14 @@ function assemble_a_path_from_fragments(fragments, rightmost=true, startfrag=0,
         let(
             // Found fragment intersects with initial path
             hitidx = select(hits,-1),
-            newpath = list_head(path,hitidx),
+            newpath = slice(path,0,hitidx+1),
             newfrags = concat(len(newpath)>1? [newpath] : [], remainder),
             outpath = concat(slice(path,hitidx,-2), foundfrag)
         )
         [outpath, newfrags]
     ) : let(
         // Path still incomplete.  Continue building it.
-        newpath = concat(path, list_tail(foundfrag)),
+        newpath = concat(path, slice(foundfrag, 1, -1)),
         newfrags = concat([newpath], remainder)
     )
     assemble_a_path_from_fragments(
@@ -1244,7 +1244,7 @@ module path_spread(path, n, spacing, sp=undef, rotate_children=true, closed=fals
         list_range(s=sp, step=spacing, e=length)
     ) : is_def(n) && is_undef(spacing)? (
         closed?
-            let(range=list_range(s=0,e=length, n=n+1)) list_head(range) :
+            let(range=list_range(s=0,e=length, n=n+1)) slice(range,0,-2) :
             list_range(s=0, e=length, n=n)
     ) : (
         let(
@@ -1426,14 +1426,14 @@ function path_cut(path,cutdist,closed) =
       cuts = len(cutlist)
   )
   [
-      [ each list_head(path,cutlist[0][1]-1),
+      [ each slice(path,0,cutlist[0][1]),
         if (!approx(cutlist[0][0], path[cutlist[0][1]-1])) cutlist[0][0]
       ],
       for(i=[0:1:cuts-2])
           cutlist[i][0]==cutlist[i+1][0] ? []
           :
           [ if (!approx(cutlist[i][0], select(path,cutlist[i][1]))) cutlist[i][0],
-            each slice(path, cutlist[i][1], cutlist[i+1][1]),
+            each slice(path,cutlist[i][1], cutlist[i+1][1]),
             if (!approx(cutlist[i+1][0], select(path,cutlist[i+1][1]-1))) cutlist[i+1][0],
           ],
       [

polyhedra.scad

@@ -699,8 +699,7 @@ function regular_polyhedron_info(
         face_normals,
         radius_scale*entry[in_radius]
     ] :
-    // info == "vnf" ? [move(translation,p=scaled_points), stellate ? faces : face_triangles] :
-    info == "vnf" ? [move(translation,p=scaled_points), faces] :
+    info == "vnf" ? [move(translation,p=scaled_points), stellate ? faces : face_triangles] : 
     info == "vertices" ? move(translation,p=scaled_points) :
     info == "faces" ? faces :
     info == "face normals" ? face_normals :

regions.scad

@@ -88,7 +88,7 @@ function check_and_fix_path(path, valid_dim=undef, closed=false, name="path") =
             is_list(valid_dim) ? str("one of ",valid_dim) : valid_dim
         )
     )
-    closed && approx(path[0], last(path))? list_head(path) : path;
+    closed && approx(path[0],select(path,-1))? slice(path,0,-2) : path;
 
 
 // Function: cleanup_region()

rounding.scad

@@ -413,7 +413,7 @@ function _rounding_offsets(edgespec,z_dir=1) =
         assert(argsOK,str("Invalid specification with type ",edgetype))
         let(
                 offsets =
-                        edgetype == "profile"? scale([-1,z_dir], p=list_tail(points)) :
+                        edgetype == "profile"? scale([-1,z_dir], p=slice(points,1,-1)) :
                         edgetype == "chamfer"?  chamf_width==0 && chamf_height==0? [] : [[-chamf_width,z_dir*abs(chamf_height)]] :
                         edgetype == "teardrop"? (
                                 radius==0? [] : concat(

shapes2d.scad

@@ -533,7 +533,7 @@ module dashed_stroke(path, dashpat=[3,3], width=1, closed=false) {
 function arc(N, r, angle, d, cp, points, width, thickness, start, wedge=false, long=false, cw=false, ccw=false, endpoint=true) =
     assert(is_bool(endpoint))
     !endpoint ? assert(!wedge, "endpoint cannot be false if wedge is true")
-               list_head(arc(N,r,angle,d,cp,points,width,thickness,start,wedge,long,cw,ccw,true)) :
+               slice(arc(N,r,angle,d,cp,points,width,thickness,start,wedge,long,cw,ccw,true),0,-2) :
     assert(is_undef(N) || is_integer(N), "Number of points must be an integer")
     // First try for 2D arc specified by width and thickness
     is_def(width) && is_def(thickness)? (
@@ -851,7 +851,7 @@ function _turtle_command(command, parm, parm2, state, index) =
         )
         list_set(
             state, [path,step], [
-                concat(state[path], list_tail(arcpath)),
+                concat(state[path], slice(arcpath,1,-1)),
                 rot(lrsign * myangle,p=state[step],planar=true)
             ]
         ) :
@@ -877,7 +877,7 @@ function _turtle_command(command, parm, parm2, state, index) =
         )
         list_set(
             state, [path,step], [
-                concat(state[path], list_tail(arcpath)),
+                concat(state[path], slice(arcpath,1,-1)),
                 rot(delta_angle,p=state[step],planar=true)
             ]
         ) :

tests/test_arrays.scad

@@ -27,6 +27,21 @@ module test_select() {
 }
 test_select();
 
+module test_last() {
+    list = [1,2,3,4];
+    assert(last(list)==4);
+    assert(last([])==undef);
+}
+test_last();
+
+module test_delete_last() {
+    list = [1,2,3,4];
+    assert(delete_last(list) == [1,2,3]);
+    assert(delete_last([1]) == []);
+    assert(delete_last([]) == []);
+}
+test_delete_last();
+
 
 module test_slice() {
     assert(slice([3,4,5,6,7,8,9], 3, 5) == [6,7]);
@@ -39,42 +54,6 @@ module test_slice() {
 test_slice();
 
 
-module test_last() {
-    list = [1,2,3,4];
-    assert(last(list)==4);
-    assert(last([])==undef);
-}
-test_last();
-
-
-module test_list_head() {
-    list = [1,2,3,4];
-    assert_equal(list_head(list), [1,2,3]);
-    assert_equal(list_head([1]), []);
-    assert_equal(list_head([]), []);
-    assert_equal(list_head(list,-3), [1,2]);
-    assert_equal(list_head(list,1), [1,2]);
-    assert_equal(list_head(list,2), [1,2,3]);
-    assert_equal(list_head(list,6), [1,2,3,4]);
-    assert_equal(list_head(list,-6), []);
-}
-test_list_head();
-
-
-module test_list_tail() {
-    list = [1,2,3,4];
-    assert_equal(list_tail(list), [2,3,4]);
-    assert_equal(list_tail([1]), []);
-    assert_equal(list_tail([]), []);
-    assert_equal(list_tail(list,-3), [2,3,4]);
-    assert_equal(list_tail(list,2), [3,4]);
-    assert_equal(list_tail(list,3), [4]);
-    assert_equal(list_tail(list,6), []);
-    assert_equal(list_tail(list,-6), [1,2,3,4]);
-}
-test_list_tail();
-
-
 module test_in_list() {
     assert(in_list("bar", ["foo", "bar", "baz"]));
     assert(!in_list("bee", ["foo", "bar", "baz"]));

turtle3d.scad

@@ -540,28 +540,28 @@ function _turtle3d_command(command, parm, parm2, state, index) =
     command=="addlength" ?  list_set(state, movestep, state[movestep]+parm) :
     command=="arcsteps" ?  assert(is_int(parm) && parm>0, str("\"",command,"\" requires a postive integer argument at index ",index))
                            list_set(state, arcsteps, parm) :
-    command=="roll" ? list_set(state, trlist, concat(list_head(state[trlist]), [lastT*xrot(parm)])):
+    command=="roll" ? list_set(state, trlist, concat(slice(state[trlist],0,-2), [lastT*xrot(parm)])):
     in_list(command,["right","left","up","down"]) ? 
-        list_set(state, trlist, concat(list_head(state[trlist]), [lastT*_turtle3d_rotation(command,default(parm,state[angle]))])):
+        list_set(state, trlist, concat(slice(state[trlist],0,-2), [lastT*_turtle3d_rotation(command,default(parm,state[angle]))])):
     in_list(command,["xrot","yrot","zrot"]) ?
         let(
              Trot = _rotpart(lastT),      // Extract rotational part of lastT
              shift = _transpart(lastT)    // Translation part of lastT
         )
-        list_set(state, trlist, concat(list_head(state[trlist]),
+        list_set(state, trlist, concat(slice(state[trlist],0,-2),
                                        [move(shift)*_turtle3d_rotation(command,default(parm,state[angle])) * Trot])):
     command=="rot" ?
         let(
              Trot = _rotpart(lastT),      // Extract rotational part of lastT
              shift = _transpart(lastT)    // Translation part of lastT
         )
-        list_set(state, trlist, concat(list_head(state[trlist]),[move(shift) * parm * Trot])):
+        list_set(state, trlist, concat(slice(state[trlist],0,-2),[move(shift) * parm * Trot])):
     command=="setdir" ?
         let(
              Trot = _rotpart(lastT),
              shift = _transpart(lastT)
         )
-        list_set(state, trlist, concat(list_head(state[trlist]),
+        list_set(state, trlist, concat(slice(state[trlist],0,-2),
                                        [move(shift)*rot(from=apply(Trot,RIGHT),to=parm) * Trot ])):
     in_list(command,["arcleft","arcright","arcup","arcdown"]) ?
         assert(is_num(parm),str("\"",command,"\" command requires a numeric radius value at index ",index))

version.scad

@@ -6,7 +6,7 @@
 //////////////////////////////////////////////////////////////////////
 
 
-BOSL_VERSION = [2,0,597];
+BOSL_VERSION = [2,0,595];
 
 
 // Section: BOSL Library Version Functions