take value from lookup column conditional on other lookup column that is matching column names from other dataframe

Question

I have this dataframe:

df <- tribble(
  ~original1,   ~original2,
1,  3,
2,  4)

  original1 original2
      <dbl>     <dbl>
1         1         3
2         2         4

and I have this lookup table:

lookup <- structure(list(original_names = c("original1", "original2", "original3"
), handy_names = c("handy_original1", "handy_original2", "handy_original3"
), label_names = c("label_original1", "label_original2", "label_original3"
)), class = "data.frame", row.names = c(NA, -3L))

  original_names     handy_names     label_names
1      original1 handy_original1 label_original1
2      original2 handy_original2 label_original2
3      original3 handy_original3 label_original3

I want to assign label_names as label attribute to dataframe df

I have tried so far:

library(sjlabelled)
library(dplyr)
df %>% 
  set_label(label = lookup$label_names[lookup$original_names %in% names(df)])

# gives
> get_label(df)
original1 original2 
       ""        "" 

My desired output

> get_label(df)
original1         original2 
"label_original1" "label_original2" 

Answer 1

Try the assignment

set_label(df) <- lookup$label_names[lookup$original_names %in% names(df)]

-testing

> get_label(df)
        original1         original2 
"label_original1" "label_original2" 

---

Note that when we are using set_label, it is not assigning in place, i.e. we may need to assign back to 'df'

library(dplyr)
df <- df %>% 
  set_label(label = lookup$label_names[lookup$original_names %in% names(df)])

Now check

> get_label(df)
        original1         original2 
"label_original1" "label_original2"