presto-geospatial/src/main/java/io/prestosql/plugin/geospatial/GeoFunctions.java/GeoFunctions/stXMin
class GeoFunctions:    @SqlNullable
    @Description("Returns X minima of a bounding box of a Geometry")
    @ScalarFunction("ST_XMin")
    @SqlType(DOUBLE)
    public static Double stXMin(@SqlType(GEOMETRY_TYPE_NAME) Slice input)
    {
        Envelope envelope = deserializeEnvelope(input);
        if (envelope == null) {
            return null;
        }
        return envelope.getXMin();
    }