when<TResult extends Object?> method

  1. @optionalTypeArgs
TResult when<TResult extends Object?>({
  1. required TResult primitive(
    1. LexPrimitive data
    ),
  2. required TResult ipld(
    1. LexIpld data
    ),
  3. required TResult blob(
    1. LexBlob data
    ),
  4. required TResult refVariant(
    1. LexRefVariant data
    ),
})

A switch-like method, using callbacks.

As opposed to map, this offers destructuring. It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case Subclass2(:final field2):
    return ...;
}

Implementation

@optionalTypeArgs TResult when<TResult extends Object?>({required TResult Function( LexPrimitive data)  primitive,required TResult Function( LexIpld data)  ipld,required TResult Function( LexBlob data)  blob,required TResult Function( LexRefVariant data)  refVariant,}) {final _that = this;
switch (_that) {
case ULexArrayItemPrimitive():
return primitive(_that.data);case ULexArrayItemIpld():
return ipld(_that.data);case ULexArrayItemBlob():
return blob(_that.data);case ULexArrayRefVariant():
return refVariant(_that.data);case _:
  throw StateError('Unexpected subclass');

}
}