This makes it easier to get upCounts aligned, as they will follow the same paradigm as fields. It also allows debug information to be shown as to where lets are added in the tree. Mote, however, that lets do not always behave as fields: even if the same let is added into the same struct multiple times, the various instance should be treated as unique fields and should not be unified. For this purpose, the old cache is still used. Fixes #1828 Signed-off-by: Marcel van Lohuizen <mpvl@gmail.com> Change-Id: Ifa459a2f0f16b2cf57c72c45a1f7b906326527b7 Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/543362 Reviewed-by: Roger Peppe <rogpeppe@gmail.com> TryBot-Result: CUEcueckoo <cueckoo@cuelang.org>