How to include an argument from another function into a new function

Question

I am trying to wrap a function from tidyr into my new function but one argument is being ignored. See example below:

library(tidyr)

one2many2 <- function(data, var) {
  data <- data %>%
    mutate(rows = row_number()) %>%
    uncount(data[, var])
  return(data)
}

a <- data.frame(name = c("Maria", "Tina"), age = c(5, 3))

The variable "age" should be removed automatically because .remove = TRUE is the default. However, "age" is still shown on the final output. How can I include the option to remove or not to remove in my function?

one2many2(a, "age", .remove = TRUE) # remove = TRUE is ignored

Answer 1

.remove works only if weights is the name of a column in data. What you set weights = data[, var] is actually evaluated as a vector of weights (weights = c(5, 3)), instead of the name of a column (weights = age). You should use Embrace operator {{ to transport a data-masked argument.

library(tidyr)

one2many2 <- function(data, var, ...){
  data %>%
    mutate(rows = row_number()) %>%
    uncount({{ var }}, ...)
}

one2many2(a, age) # no need to quote "age"
#    name rows
# 1 Maria    1
# 2 Maria    1
# 3 Maria    1
# 4 Maria    1
# 5 Maria    1
# 6  Tina    2
# 7  Tina    2
# 8  Tina    2

one2many2(a, age, .remove = FALSE)
#    name age rows
# 1 Maria   5    1
# 2 Maria   5    1
# 3 Maria   5    1
# 4 Maria   5    1
# 5 Maria   5    1
# 6  Tina   3    2
# 7  Tina   3    2
# 8  Tina   3    2