How to use with

use_with.R

foo <- function(x) {
  d <- "r"
  s <- with(x , {
    r <- if (exists("a", inherits = FALSE)) {
      a + b
    } else {
      0
    }
    dd <- if (exists("d", inherits = FALSE)) {
      1
    } else {
      0
    }
    list(r, dd)
    
    })
  
  s
}

zz <- list(a = 1 , b = 3)
foo(zz)



goo <- \(x, ...) {
  q <-  1
  r <-  "H"
  tee()
}


tee <- \() {
  parent.frame()  |> 
    as.list()
    
}

goo(3)