An option represents an immediate value that might be
, or not be present.
This differentiates from just using A | null in two
particular cases:
When strict null check is not enabled.
When null may be a present, valid value.
This makes the option<A> type specially useful, because
the option type states explicitly if the value is present
as meant, or otherwise not, even if undefined is a
valid case value.
Type Parameters
A
Example
leta: option<number> = maybe() if (a.isPresent()) { // Here a is `some<A>`, which means that has a value. }
Option
An option represents an immediate value that might be , or not be present.
This differentiates from just using
A | nullin two particular cases:This makes the
option<A>type specially useful, because the option type states explicitly if the value is present as meant, or otherwise not, even ifundefinedis a valid case value.