This feature is experimental. It may be changed or removed in a future version.
Makes the cache assume that newRequest has the same response as the already cached oldRequest.
newRequest
oldRequest
Unpoly uses this internally when the user redirects from /old to /new. In that case, both /old and /new will cache the same response from /new.
/old
/new
The earlier request or request options.
The new request or request options.
If oldRequest wasn't found in the cache, undefined is returned.
undefined
