Merge branch '21-scalars' into 23
Merge branch '16-t-varop-mm' into 23
Merge branch '21-misc-cleanup' into 23
Merge branch '21-misc-cleanup' into 23
Merge branch '21-misc-cleanup' into 23
revise applydefine scheme, fix bug, add test of bug
Merge branch '23-applydefine' into 25
no duplicate in EnsureLocal, related mods, speedup of length<-
Merge branch '23-applydefine' into 25