when<TResult extends Object?>  method 
      
  
TResult
when<TResult extends Object?>()
      
      
    
A switch-like method, using callbacks.
As opposed to map, this offers destructuring.
It is equivalent to doing:
switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case Subclass2(:final field2):
    return ...;
}
Implementation
@optionalTypeArgs TResult when<TResult extends Object?>(TResult Function(@JsonKey(name: 'crv')  String crv, @JsonKey(name: 'ext')  bool ext, @JsonKey(name: 'key_ops')  List<String> keyOps, @JsonKey(name: 'kty')  String kty, @JsonKey(name: 'x')  String x, @JsonKey(name: 'y')  String y)  $default,) {final _that = this;
switch (_that) {
case _PublicKey():
return $default(_that.crv,_that.ext,_that.keyOps,_that.kty,_that.x,_that.y);}
}