whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? account(
    1. SplTokenAccountDataInfo info,
    2. String type,
    3. String? accountType
    )?,
  2. TResult? mint(
    1. MintAccountDataInfo info,
    2. String type,
    3. String? accountType
    )?,
  3. TResult? unknown(
    1. String type
    )?,
})

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( SplTokenAccountDataInfo info,  String type,  String? accountType)?  account,TResult? Function( MintAccountDataInfo info,  String type,  String? accountType)?  mint,TResult? Function( String type)?  unknown,}) {final _that = this;
switch (_that) {
case TokenAccountData() when account != null:
return account(_that.info,_that.type,_that.accountType);case MintAccountData() when mint != null:
return mint(_that.info,_that.type,_that.accountType);case UnknownAccountData() when unknown != null:
return unknown(_that.type);case _:
  return null;

}
}