Function useHaystackPoint

useHaystackPoint<Value extends HVal>(
    originaryPoint: Optional<Point<Value>>,
    pollRate?: number,
    writeOptions?: HaystackPointWriteOptions,
): [
    Optional<Value>,
    PointWriteFunc<Value> | undefined,
    Optional<Point<Value>>,
]
A hook that allows using a point from an haystack server as react state.

Important: This hooks requires a ClientContext to work.
Type Parameters
- Value extends HVal
Parameters
- originaryPoint: Optional<Point<Value>>
  point dict used to retrieve its id and initial value.
- pollRate: number = 5
  poll rate for the value subscription. Expressed in seconds.
- OptionalwriteOptions: HaystackPointWriteOptions
  default options for the write callback.
Returns [Optional<Value>, PointWriteFunc<Value> | undefined, Optional<Point<Value>>]
Returns the point value, a function to update it and the point dict.
See
https://github.com/j2inn/haystack-nclient
Example: Example of usage with a numeric point.
```
const point= useReadByFilter('point and temp and zone and sp').grid[0] // One-shot reading the first point that matches the filter
const [pointValue, setPointValue, updatedPoint] = useHaystackPoint<HNum>(point) // Using the point state
```
- Defined in src/useHaystackPoint.ts:39