implement conversion from multipolygon to polygon of length one about geo HOT 2 OPEN

A MultiPolygon is implemented as a Vec of Polygons, so if you need an object of Polygon, you can take the Polygon from the inner Vec.

use geo::{MultiPolygon, Polygon, polygon};

let mut multi_polygon: MultiPolygon = MultiPolygon::new(vec![polygon![(x: 0.0, y: 0.0), (x: 2.0,  y: 0.0), (x: 1.0, y: 2.0)]]);
let polygon: Polygon = multi_polygon.0.remove(0);
println!("polygon: {:?}", polygon);

If that's not what you mean, could you please clarify by providing some example code that you'd like to be able to write, but currently cannot.

from geo.

Yeah, quite similar. I'd like some syntax like below, preferably. Where the Result panics if the inner vector is greater than length 1.

use geo::{MultiPolygon, Polygon, polygon};

let multi_polygon: MultiPolygon = MultiPolygon::new(vec![polygon![(x: 0.0, y: 0.0), (x: 2.0,  y: 0.0), (x: 1.0, y: 2.0)]]);

let inner_poly: Polygon = multi_polygon.try_from().unwrap();

from geo.