Keeping data when using mapply in R

Question

I have a data frame I am applying a function to using mapply(), but my result doesn't keep certain info in the initial data frame that I would like to keep. The function I am applying across the data frame is not vectorized.

DATA FRAME

Dealer  Cities                  Zip     Radius in miles     
A       Rancho Cucamonga, CA    91730   40  
A       San Bernardino, CA      92401   40  
B       Chino, CA               91710   40  
B       Fontana, CA             92337   40  

I am applying a function that gets all zip codes in the given mile radius of the initial zip.

remotes::install_github("EAVWing/ZipRadius")

results <-  with(city_names, mapply(ZipRadius::zipRadius, 
                             as.character(`Center Zip Code`),`Radius in miles`, SIMPLIFY =FALSE ))

RESULT

The result is a large list containing a data frame for each time the function zipRadius was called.

DESIRED RESULT

Each data frame contains the zip code used by the function and the data the function generates, but I would like it to also keep the corresponding "Dealer" column associated with each initial Zip.

For example, the above data frame is generated from the zip 91730, which has a Dealer value of A.

DEALER   ZIP      Other columns generated by the function...
A        90001 
A        90002
A        90011

Answer 1

@Onyambu gave me a great solution in the comments (source):

dplyr::left_join(city_names, dplyr::bind_rows(results, .id ='zip1'),  
                  by =c(Zip= 'zip1'))