    path.length([opt])

Return the length of the path.

The path length is a sum of the lengths of visible path segments; invisible segments (e.g. Moveto segments) have a length of 0. If the path has no segments at all, `0` is returned.

Although calculating the length of linear segments (e.g. Lineto and Closepath segments) is straightforward, determining the length of curved segments is complex. Refer to `curve.length()` documentation for more information.

The `opt` argument is optional. Two properties may be specified, `opt.precision` and `opt.segmentSubdivisions`, which determine maximum error allowed for the length calculation (default precision is 3; this corresponds to maximum observed error of 0.1%). The `opt.segmentSubdivisions` property is an array of individual segments' subdivision arrays. The `path.getSegmentSubdivisions()` function may be used to obtain the `segmentSubdivisions` array.