Removal of features without warning (Path.closed)

Dear @regebro, I was very happy to find your library and I am using it in several projects: NNGT and DeNSE (as it was an optional dependency it does not appear in the manifest though, so GitHub does not know about it for its dependency graph).

This is just to let you know that, as a dependency published on PyPI, I would expect features such as the closed property of path to be deprecated before being removed, so as to not break code immediately for everyone who might be using the library.

Am I correct in thinking that this could have been kept using

    @property
    def closed(self):
        return isinstance(self, Close)

as an object property?

[tatarize]

Here’s some functions to make the code easier if you want:

from svg.path import Move, Close, Path

def get_subpaths(path):
    segments = None
    for p in path:
        if isinstance(p, Move):
            if segments is not None:
                raise RuntimeError("Only closed shapes accepted.")
            segments = []
        segments.append(p)
        if isinstance(p, Close):
            yield Path(*segments)
            segments = None


def get_points(path, interpolate_curve=50):
    points = []
    for item in path:
        if isinstance(item, (Arc, CubicBezier, QuadraticBezier)):
            istart = 1. / interpolate_curve
            for frac in np.linspace(istart, 1, interpolate_curve):
                points.append(
                    (item.point(frac).real, item.point(frac).imag))
        else:
            points.append((item.start.real, item.start.imag))
    return points

Which could use the start code block:

        path_data = parse_path(instructions["path"])
        subpaths = [subpath for subpath in get_subpaths(path_data)]
        shell = get_points(subpaths[0], interpolate_curve)  # the first path is the outer shell?
        holes = [get_points(subpath) for subpath in subpaths[1:]]
        shell = np.array(shell)
        container = Polygon(shell, holes=holes)

[tatarize]

https://xkcd.com/1172/