Function yieldNumber

yieldNumber(generator, defaultValue?): (() => undefined | number)
Returns a function that yields a value from a generator.
```
const spring = yieldNumber(Oscillators.spring());

spring(); // latest value
```
Instead of:
```
const spring = Oscillators.spring();

spring.next().value
```
A defaultValue can be provided if the source generator returns undefined:
```
const spring = yieldNumber(Oscillators.spring(), 0);
spring(); // Returns 0 if the generator returns undefined
```
Parameters
- generator: Generator<number, any, unknown>
- OptionaldefaultValue: number
Returns (() => undefined | number)
- - (): undefined | number
  - Returns undefined | number