whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? splToken(
    1. SplTokenProgramAccountData parsed
    )?,
  2. TResult? token2022(
    1. SplTokenProgramAccountData parsed
    )?,
  3. TResult? stake(
    1. StakeProgramAccountData parsed
    )?,
  4. TResult? unsupported(
    1. Map<String, dynamic> parsed
    )?,
})

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( SplTokenProgramAccountData parsed)?  splToken,TResult? Function( SplTokenProgramAccountData parsed)?  token2022,TResult? Function( StakeProgramAccountData parsed)?  stake,TResult? Function( Map<String, dynamic> parsed)?  unsupported,}) {final _that = this;
switch (_that) {
case ParsedSplTokenProgramAccountData() when splToken != null:
return splToken(_that.parsed);case ParsedSplToken2022ProgramAccountData() when token2022 != null:
return token2022(_that.parsed);case ParsedStakeProgramAccountData() when stake != null:
return stake(_that.parsed);case UnsupportedProgramAccountData() when unsupported != null:
return unsupported(_that.parsed);case _:
  return null;

}
}