how animate a shape with a path

I draw a line with Shape, I want to change it with the time, how do I do?

I've try:

`
let s=new Zdog.Shape({
addTo: illo,
path: [ // triangle
{ x: 0, y: -40 },
{ x: 40, y: 40 },
{ x: -40, y: 40 },
],
closed: false, // unclosed
stroke: 20,
color: '#636'
});
s.path= [ // triangle
{ x: 0, y: -90 },
{ x: 10, y: 40 },
{ x: -40, y: 40 },
]`

but it seems that the new value of path is not updated :(

Start by tracing how Zdog.Shape handles the path property and how the illo is updated or rendered after the shape is created. Reproduce the reported reassignment with the supplied triangle example and determine what behavior should confirm that the path change is applied.

Written by the indexing model from the issue text.