Function isNone

isNone<T>(val): val is NoneOption<T>
Type guard to check if an Option is a None value. This function is used to narrow down the type of an Option to NoneOption in TypeScript's type system.
Type Parameters
- T extends NonUndefined
Parameters
- val: Option<T>
  The Option to be checked.
Returns val is NoneOption<T>
true if the provided Option is a NoneOption, false otherwise.

Example
```
const option = None;
if (isNone(option)) {
  console.log('Option does not have a value.');
}
```
Deprecated
Use Option.isNone instead.
- Defined in option/option.ts:395