mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? error(
    1. WsErrorMsg value
    )?,
  2. TResult? block(
    1. WsMsgBlockClient value
    )?,
  3. TResult? tx(
    1. WsMsgTxClient value
    )?,
})

A variant of map that fallback to returning null.

It is equivalent to doing:

switch (sealedClass) {
  case final Subclass value:
    return ...;
  case _:
    return null;
}

Implementation

@optionalTypeArgs TResult? mapOrNull<TResult extends Object?>({TResult? Function( WsErrorMsg value)?  error,TResult? Function( WsMsgBlockClient value)?  block,TResult? Function( WsMsgTxClient value)?  tx,}){
final _that = this;
switch (_that) {
case WsErrorMsg() when error != null:
return error(_that);case WsMsgBlockClient() when block != null:
return block(_that);case WsMsgTxClient() when tx != null:
return tx(_that);case _:
  return null;

}
}