# isRellOperation · FT4 TypeScript client · Chromia Docs (concept)

> isRellOperation(op: RellOperation | Operation): op is RellOperation Type assertion to assert if the provided value is an Operation or a RellOperation Param

Source: https://docs.chromia.com/pages/ft4-ts-client/functions/utils.isRellOperation/

Function

# isRellOperation

* ```signature
  isRellOperation(op: RellOperation | Operation): op is RellOperation
  ```

  Type assertion to assert if the provided value is an `Operation` or a `RellOperation`

  #### Parameters

  + op: RellOperation | Operation

    the value to assert

  #### Returns op is RellOperation

  true if the provided value is a `RellOperation`

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-ts-client/functions/utils.isRellOperation.html)Generated API reference, mirrored from the live docs