Another riff on the placeholder idea with |>:

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
. <- function(.dat, template){
    template_code <- deparse(substitute(template)) 
    arg <- deparse(substitute(.dat))
    interpolated_code <- gsub("(?<=[(, ])?[.](?=[), \\[])", arg, template_code, perl = TRUE)
    eval(parse( text = interpolated_code))
}

"a" |>
 .(c(., "b")) |>
 .(setNames(., .))
#>   a   b 
#> "a" "b"

mtcars |> 
    transform(kmL = mpg / 2.35) |>
    .(lm(kmL ~ hp, data = .))
#> 
#> Call:
#> lm(formula = kmL ~ hp, data = transform(mtcars, kmL = mpg/2.35))
#> 
#> Coefficients:
#> (Intercept)           hp  
#>    12.80803     -0.02903

"col_name" |> 
  .(mutate(mtcars, . = "cool")) |>
  .(bind_cols(., .)) |>
  .(.[1, ])
#> New names:
#> * mpg -> mpg...1
#> * cyl -> cyl...2
#> * disp -> disp...3
#> * hp -> hp...4
#> * drat -> drat...5
#> * ...
#>           mpg...1 cyl...2 disp...3 hp...4 drat...5 wt...6 qsec...7 vs...8
#> Mazda RX4      21       6      160    110      3.9   2.62    16.46      0
#>           am...9 gear...10 carb...11 col_name...12 mpg...13 cyl...14 disp...15
#> Mazda RX4      1         4         4          cool       21        6       160
#>           hp...16 drat...17 wt...18 qsec...19 vs...20 am...21 gear...22
#> Mazda RX4     110       3.9    2.62     16.46       0       1         4
#>           carb...23 col_name...24
#> Mazda RX4         4          cool

^{Created on 2021-06-24 by the reprex package (v2.0.0)}

I call . the ‘neutering’ function.