Capture the name of an input value in a function

user_7223434 0
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I was wondering if there is a way to capture the input to the argument study_id in my function below.

For example, my desired output in the below example is: "study". Is this possible?

library(rlang)

foo <- function(data, study_id){
  
  study_id <- ensym(study_id)
  
# names(data[study_id]) # I tried this without success
}
  
# EXAMPLE OF USE:

dat = data.frame(a=1:3,study=4:6)

foo(dat, study_id = study)

# DESIRED OUTPUT:

> [1] "study"
rlang tidyverse dataframe r function
1 Answers

We could use as_string

foo <- function(data, study_id){
  
  study_id <- ensym(study_id)
  
  as_string(study_id)
}

-testing

foo(dat, study_id = study)
[1] "study"

In base R, this can be done with deparse/substitute

foo1 <- function(data, study_id) deparse(substitute(study_id))
foo1(dat, study_id = study)
[1] "study"
user_37322710
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