lazy_bindings

create_lazy_bindings <- function(x, ...){
  environment()
}

# object df is in the environment but has not been evaluated
e <- create_lazy_bindings(y)
ls(e)
#> [1] "x"

# thus this won't work
as.list(e)
#> Error in as.list.environment(e): objet 'y' introuvable

# but this does!
evalq(substitute(x), envir = e)
#> y

# it also works with the dots!
e <- create_lazy_bindings(cars, speed < 5)
evalq(subset(cars, ...), envir = e)
#>   speed dist
#> 1     4    2
#> 2     4   10

# and you can even use lazy binding in the global environment!
... <- e$...
subset(cars, ...)
#>   speed dist
#> 1     4    2
#> 2     4   10

a <- 1
b <- 2
e <- create_lazy_bindings(a + b)
a <- 100
z <- e$x
a <- 1000
z
#> [1] 102