The error that occurred during the operation execution. This can be a
CombinedGraphQLErrors instance (for GraphQL errors) or another error
type (for network errors).
Use CombinedGraphQLErrors.is(error) to check if it's a GraphQL error with an errors array.
A function that calls the next link in the link chain. Calling
return forward(operation) in your ErrorLink callback
retries the operation, returning a new observable for the
upstream link to subscribe to.
The details of the GraphQL operation that produced an error.
OptionalresultThe raw GraphQL result from the server (if available), which may include partial data alongside errors.
The object provided to the
ErrorHandlercallback function.