Function useHaystackRecordTag

useHaystackRecordTag<Value>(originalRecord?: Record, tagName?: string, pollRate?: number): [Optional<Value>, RecordTagWriteFunc<Value> | undefined, Optional<Record>]
A hook to use a record tag from an haystack server as react state.

IMPORTANT: writing is currently only supported with a FIN 5/SkySpark server.

IMPORTANT: This hooks requires a ClientContext to work.

See
https://github.com/j2inn/haystack-nclient

Example
Example of usage for a precision tag of type Number.
```
const record = useReadByFilter('precision and point and temp and zone and sp').grid[0] // One-shot reading the first record that matches the filter
const [precision, setPrecision, updatedRecord] = useHaystackRecordTag<HNum>(record, "precision") // Using its tag state
```
Returns
Returns the point value, a function to update it and the point dict.
Type Parameters
Type Parameters
- Value extends HVal<Value>
Parameters
- Optional originalRecord: Record
  
  record dict used to retrieve id and initial value.
- Optional tagName: string
  
  name of the tag.
- pollRate: number = 5
  
  poll rate for the value subscription. Expressed in seconds.
Returns [Optional<Value>, RecordTagWriteFunc<Value> | undefined, Optional<Record>]
- Defined in src/useHaystackRecordTag.ts:37