None
This type represents no value.
This is a pair of Some(T)
.
You can create this type value and get an inner value in this type by hand. But we recommend to use factory and utility functions for forward compatibility. And we don't recommend to implement this type for your type too.
- {@link createNone()} to create a value of
None
. - {@link isNone()} to check whether the value is
None
. - ...and more.
§Properties
Don't touch this property directly from an user project except 3rd party project that does not install this package but uses a value returned from an other project. Instead, use {@link isSome()} or {@link isNone()} operator to get an inner value.
Historically, this type was created to target a JSVM that supports ES5.
Then there was no well optimized Symbol
to achieve a private property.
We don't have a plan to change this into private property keep the backward compatibility.
Don't touch this property directly from an user project except 3rd party project that does not install this package but uses a value returned from an other project. Instead, use {@link unwrapSome()} operator to get an inner value.
Historically, this type was created to target a JSVM that supports ES5.
Then there was no well optimized Symbol
to achieve a private property.
We don't have a plan to change this into private property keep the backward compatibility.