Defusing numbered dots

[lionel-]

This should capture foo:

f <- function(...) enquo(..1)
f(foo)
#> Error in (function (arg)  : object '..1' not found

When match.call() matches dots, it creates numbered dots like ..1 or ..2. Currently enquo() and enquos() don't handle these. This makes it difficult to use call-matching idioms which are sometimes useful (I think call-matching would be helpful to solve tidyverse/dplyr#5815).

defuser <- function(...) enquos(...)


### Expected output

wrapper <- function(...) {
  foo <- 1
  defuser(..., y = foo)
}
local({
  bar <- 10
  wrapper(x = bar)
})
#> <list_of<quosure>>
#>
#> $x
#> <quosure>
#> expr: ^bar
#> env:  0x7fa13f27b040
#>
#> $y
#> <quosure>
#> expr: ^foo
#> env:  0x7fa13f27add8


### Problematic output

wrapper2 <- function(...) {
  foo <- 1
  eval(match.call(
    defuser,
    quote(defuser(..., y = foo)),
    envir = environment()
  ))
}
local({
  bar <- 10
  wrapper2(x = bar)
})
#> <list_of<quosure>>
#>
#> $x
#> <quosure>
#> expr: ^..1
#> env:  0x7fa1488cb438
#>
#> $y
#> <quosure>
#> expr: ^foo
#> env:  0x7fa1488cb438