diff --git a/src/examples.rs b/src/examples.rs
index 28ada6b..9c4f1e0 100644
--- a/src/examples.rs
+++ b/src/examples.rs
@@ -50,12 +50,13 @@ pub fn cube_thing() -> Rule<()> {
 
 pub fn barbs() -> Rule<()> {
 
-    let (b0, b1);
+    let (b0, bn);
     let base_verts: Vec<VertexUnion> = vec_indexed![
-        @b0: VertexUnion::Vertex(vertex(-0.5, -0.5, 0.0)),
-             VertexUnion::Vertex(vertex(-0.5,  0.5, 0.0)),
-             VertexUnion::Vertex(vertex( 0.5,  0.5, 0.0)),
-        @b1: VertexUnion::Vertex(vertex( 0.5, -0.5, 0.0)),
+        @b0 VertexUnion::Vertex(vertex(-0.5, -0.5, 0.0)),
+        VertexUnion::Vertex(vertex(-0.5,  0.5, 0.0)),
+        VertexUnion::Vertex(vertex( 0.5,  0.5, 0.0)),
+        VertexUnion::Vertex(vertex( 0.5, -0.5, 0.0)),
+        @bn,
     ];
     let n = base_verts.len();
 
@@ -71,7 +72,7 @@ pub fn barbs() -> Rule<()> {
             &mut (0..4).map(|i| VertexUnion::Arg(i)).collect()
         );
 
-        let geom = util::parallel_zigzag(next_verts.clone(), b0..b1+1, a0..a1);
+        let geom = util::parallel_zigzag(next_verts.clone(), b0..bn, a0..a1);
         let final_geom = MeshFunc {
             verts: (0..4).map(|i| VertexUnion::Arg(i)).collect(),
             faces: vec![ 0, 2, 1,   0, 3, 2 ],
diff --git a/src/util.rs b/src/util.rs
index 2bd933a..b7779c4 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -4,17 +4,21 @@ use crate::xform::{Vertex};
 //use crate::rule::{Rule, Child};
 
 /// This is like `vec!`, but it can handle elements that are given
-/// with `@var: element` rather than `element`, e.g. like
-/// `vec_indexed![foo, bar, @a: baz, quux]`. The variable (which must
+/// with `@var element` rather than `element`, e.g. like
+/// `vec_indexed![foo, bar, @a baz, quux]`. The variable (which must
 /// already be declared and a `usize`) is then assigned the index of the
-/// element it precedes.  This can be used any number of times with
+/// element it precedes (2).  This can be used any number of times with
 /// different elements and indices.
+///
+/// It can  also be used like `vec_indexed![foo, bar, baz, @b,]` in which
+/// case `b` is the index after 'baz' (3) rather than before. This still
+/// requires a trailing comma.
 #[macro_export]
 macro_rules! vec_indexed {
     // Thank you to GhostOfSteveJobs and Rantanen in the Rust discord.
-    ($( $(@ $Index:ident :)? $Value:expr,)*) => {{
+    ($( $(@ $Index:ident)? $($Value:expr)?,)*) => {{
         let mut v = Vec::new();
-        $( $($Index = v.len();)? v.push($Value); )*
+        $( $($Index = v.len();)? $(v.push($Value);)? )*
         v
     }};
 }