format method
Returns a formatted string representation of this rectangle.
Each component is formatted to a fixed number of decimal places.
x0 sets the default precision for all components; individual overrides
can be provided via y0, w0, and h0.
Example: [ X:<x>, Y:<y>, W:<width>, H:<height> ]
Implementation
String format([int x0 = 0, int? y0, int? w0, int? h0]) =>
'[ '
'X:${x.toStringAsFixed(x0)}, '
'Y:${y.toStringAsFixed(y0 ?? x0)}, '
'W:${width.toStringAsFixed(w0 ?? x0)}, '
'H:${height.toStringAsFixed(h0 ?? x0)} '
']';