mapOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? mapOrNull<TResult extends Object?>({
  1. TResult? immediate(
    1. ImmediateCartSummaryItem value
    )?,
  2. TResult? deferred(
    1. DeferredSummaryItem value
    )?,
  3. TResult? recurring(
    1. RecurringCartSummaryItem 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( ImmediateCartSummaryItem value)?  immediate,TResult? Function( DeferredSummaryItem value)?  deferred,TResult? Function( RecurringCartSummaryItem value)?  recurring,}){
final _that = this;
switch (_that) {
case ImmediateCartSummaryItem() when immediate != null:
return immediate(_that);case DeferredSummaryItem() when deferred != null:
return deferred(_that);case RecurringCartSummaryItem() when recurring != null:
return recurring(_that);case _:
  return null;

}
}