Any codes that have a Key "NA" get converted to NA

[rix133]

running icesVocab::getCodeList("WLTYP") works but the 13th code is empty.

the problem is that type.convert defaults na.strings = "NA" in toVocabdf

> sessionInfo()
R version 4.3.1 (2023-06-16 ucrt)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 19045)

Matrix products: default


locale:
[1] LC_COLLATE=Estonian_Estonia.utf8  LC_CTYPE=Estonian_Estonia.utf8    LC_MONETARY=Estonian_Estonia.utf8
[4] LC_NUMERIC=C                      LC_TIME=Estonian_Estonia.utf8    

time zone: Europe/Tallinn
tzcode source: internal

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
 [1] gtable_0.3.0                   dplyr_1.0.9                    compiler_4.3.1                
 [4] tidyselect_1.1.2               Rcpp_1.0.9                     xml2_1.3.3                    
 [7] assertthat_0.2.1               RDBESdataConversion_0.0.0.9000 scales_1.2.0                  
[10] readxl_1.4.0                   yaml_2.3.5                     fastmap_1.1.0                 
[13] ggplot2_3.3.6                  R6_2.5.1                       generics_0.1.3                
[16] curl_4.3.2                     classInt_0.4-7                 sf_1.0-8                      
[19] knitr_1.39                     tibble_3.1.8                   units_0.8-0                   
[22] munsell_0.5.0                  lubridate_1.8.0                DBI_1.1.3                     
[25] pillar_1.8.0                   rlang_1.0.4                    utf8_1.2.2                    
[28] xfun_0.32                      cli_3.3.0                      magrittr_2.0.3                
[31] class_7.3-20.1                 digest_0.6.29                  grid_4.3.1                    
[34] rstudioapi_0.13                lifecycle_1.0.1                icesVocab_1.2.0