fix memoise

[dpprdan]

{tidygeocoder}'s current CRAN version does not work well with {memoise}, because

you can’t have a default argument with a default value that is the same as the argument name[, no matter if it is the default or not]

(Omissions and addition mine, see below).

I.e. geo(…, lat = lat) is a problem.

library(tidygeocoder)
mgeo <- memoise::memoise(geo)
mgeo("1600 Pennsylvania Ave NW, Washington, DC")
#> Error in FUN(X[[i]], ...): promise already under evaluation: recursive default argument reference or earlier problems?

This can be fixed (mostly), if we change the defaults for lat and long to strings. With this PR we get:

library(tidygeocoder)
mgeo <- memoise::memoise(geo)
mgeo("1600 Pennsylvania Ave NW, Washington, DC")
#> Passing 1 address to the Nominatim single address geocoder
#> Query completed in: 1.3 seconds
#> # A tibble: 1 x 3
#>   address                                    lat  long
#>   <chr>                                    <dbl> <dbl>
#> 1 1600 Pennsylvania Ave NW, Washington, DC  38.9 -77.0

Unfortunately, the value may never match the argument name, default or not.

mgeocode <- memoise::memoise(geocode)
mgeocode(
  .tbl = data.frame(address = "1600 Pennsylvania Ave NW, Washington, DC"), 
  address = address
)
#> Error in FUN(X[[i]], ...): object 'address' not found

But this can be fixed by the user by passing a quoted column name.

mgeocode(
  .tbl = data.frame(address = "1600 Pennsylvania Ave NW, Washington, DC"), 
  address = 'address'
)
#> Passing 1 address to the Nominatim single address geocoder
#> Query completed in: 1 seconds
#> # A tibble: 1 x 3
#>   address                                    lat  long
#>   <chr>                                    <dbl> <dbl>
#> 1 1600 Pennsylvania Ave NW, Washington, DC  38.9 -77.0

Maybe we should add a note about this somewhere? Or is this too niche?

A second commit changes the styling of the function arguments in the source, making them (arguably) easier to find. But I can revert, if you don't agree.

(Also, TIL roxygen always uses double quotes)

[jessecambon]

@dpprdan thanks, I've pulled this in and it will be part of the v1.0.5 release. We could possibly put a note on this at the end of the vignette.

[jessecambon]

This is the note I've added:

For use with the memoise package, you may need to use character values when specifying input data columns in the geocode() and reverse_geocode() functions. See #154 for details.