julia

efc1ba90 - Move `eachregion(::AnnotatedString)` implementation to `Base` (#57912)

Move `eachregion(::AnnotatedString)` implementation to `Base` (#57912) Excising part of https://github.com/JuliaLang/julia/pull/56194/ on the way to reviving that PR. (cherry picked from commit a5e0eabfdbecc40ff9c3d4ba86a4bc76036f352e)