Err
This type contain a failure information E.
You can create this type value and get an inner value in this type by hand. But we recommend to use the factory {@link createErr()} and utility functions for forward compatibility. And we don't recommend to implement this type for your type too.
- {@link createErr()} to create a value of
Err(E). - {@link isErr()} to check whether the value is
Err(E). - {@link unwrapErr()} to get an inner failure information in
Err(E). - ...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 unwrapErr()} 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 isOk()} or {@link isErr()} 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 unwrapOk()} 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.