Function isSome

isSome<T>(maybe: Maybe<T>): maybe is Some<T>
Type-narrowing predicate: returns true when the value is Some.
Type Parameters
- T
Parameters
- maybe: Maybe<T>
Returns maybe is Some<T>
Example
```
if (isSome(m)) {
  console.log(m.value);   // narrowed to Some branch
}
```
- Defined in maybe.ts:38