local_ and with_ symmetry in withr

I was reading the withr 3.0.0 release notes and noticed a pleasing symmetry the with_ and local_ functions.

The local_ functions set a temporary value within some local scope, like a local() or a function().

local({
  withr::local_language("fr")
  plot[[1]]
})
#> Error in `plot[[1]]`:
#> ! objet de type 'closure' non indiçable
plot[[1]]
#> Error in `plot[[1]]`:
#> ! object of type 'closure' is not subsettable

The with_ functions set a temporary value around some block of code.

withr::with_language("fr", {
  plot[[1]]
})
#> Error in `plot[[1]]`:
#> ! objet de type 'closure' non indiçable
plot[[1]]
#> Error in `plot[[1]]`:
#> ! object of type 'closure' is not subsettable

So where are we working from?

• local_: within the code (scope)
• with_: around the code

Oh, and the notes for withr 3.0.0, indicates that I should keep an eye on how source() interacts with withr.