whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? deposit(
    1. String requestId,
    2. QuoteDeposit deposit
    )?,
  2. TResult? transaction(
    1. String requestId,
    2. dynamic transaction
    )?,
})

A variant of when that fallback to returning null

It is equivalent to doing:

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

Implementation

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>({TResult? Function( String requestId,  QuoteDeposit deposit)?  deposit,TResult? Function( String requestId,  dynamic transaction)?  transaction,}) {final _that = this;
switch (_that) {
case QuoteStepDeposit() when deposit != null:
return deposit(_that.requestId,_that.deposit);case QuoteStepTransaction() when transaction != null:
return transaction(_that.requestId,_that.transaction);case _:
  return null;

}
}