julia

a2be715d - gf: allow method shadowing with exact signatures without deletion (#53415)

gf: allow method shadowing with exact signatures without deletion (#53415) We already allowed method shadowing for an inexact signature and implicit method deletion by exact signatures, so it was fairly arbitrary to implement it as a deletion for a replacement by an exact signature rather than use the morespecific definition for this. This change should be useful to Mocking libraries, such as Pluto, which previously had a buggier version of this which tried to re-activate or re-define the old methods. There is a bit of code cleanup in here, either of unused features, or of aspects that were broken, or of world_valid computations that were not actually impacting the final result (e.g. when there is a more specific result matches, it does not need to limit the result valid world range because of a less specific result that does not get returned).