{{ embrace }} doesn't work with pairwise_cor()

[sebastian-fox]

Hi There,

I love your package. I can't see anything about this in the current issues. I've been trying to create a function that uses widyr::pairwise_cor() using the new tidy eval method embrace, but it doesn't work. I can't see why. Here is a reproducible example:

library(dplyr)
library(gapminder)
library(tidyr)
library(widyr)

# this works
gapminder %>%
  pairwise_cor(country, year, lifeExp)

dummy_function <- function(data, var1, var2, var3) {
  data %>%
    pairwise_cor({{ var1 }}, {{ var2 }}, {{ var3 }}) %>%
    return()
}

# this doesn't work
dummy_function(gapminder, country, year, lifeExp)

This returns:

Error: Invalid column specification 

Are you able to help?
Many thanks

Session info:

- Session info ------------------------------------------------------------------------------------------------------
 setting  value                       
 version  R version 3.6.1 (2019-07-05)
 os       Windows 10 x64              
 system   x86_64, mingw32             
 ui       RStudio                     
 language (EN)                        
 collate  English_United Kingdom.1252 
 ctype    English_United Kingdom.1252 
 tz       Europe/London               
 date     2019-09-26                  

- Packages ----------------------------------------------------------------------------------------------------------
 package     * version date       lib source        
 assertthat    0.2.1   2019-03-21 [1] CRAN (R 3.6.0)
 backports     1.1.4   2019-04-10 [1] CRAN (R 3.6.0)
 broom         0.5.2   2019-04-07 [1] CRAN (R 3.6.0)
 cli           1.1.0   2019-03-19 [1] CRAN (R 3.6.0)
 crayon        1.3.4   2017-09-16 [1] CRAN (R 3.6.0)
 dplyr       * 0.8.3   2019-07-04 [1] CRAN (R 3.6.1)
 fansi         0.4.0   2018-10-05 [1] CRAN (R 3.6.0)
 gapminder   * 0.3.0   2017-10-31 [1] CRAN (R 3.6.0)
 generics      0.0.2   2018-11-29 [1] CRAN (R 3.6.1)
 glue          1.3.1   2019-03-12 [1] CRAN (R 3.6.0)
 janeaustenr   0.1.5   2017-06-10 [1] CRAN (R 3.6.0)
 lattice       0.20-38 2018-11-04 [1] CRAN (R 3.6.1)
 lifecycle     0.1.0   2019-08-01 [1] CRAN (R 3.6.1)
 magrittr      1.5     2014-11-22 [1] CRAN (R 3.6.0)
 Matrix        1.2-17  2019-03-22 [1] CRAN (R 3.6.1)
 nlme          3.1-140 2019-05-12 [1] CRAN (R 3.6.1)
 packrat       0.5.0   2018-11-14 [1] CRAN (R 3.6.0)
 pillar        1.4.2   2019-06-29 [1] CRAN (R 3.6.0)
 pkgconfig     2.0.3   2019-09-22 [1] CRAN (R 3.6.1)
 plyr          1.8.4   2016-06-08 [1] CRAN (R 3.6.0)
 purrr         0.3.2   2019-03-15 [1] CRAN (R 3.6.0)
 R6            2.4.0   2019-02-14 [1] CRAN (R 3.6.0)
 Rcpp          1.0.2   2019-07-25 [1] CRAN (R 3.6.1)
 reshape2      1.4.3   2017-12-11 [1] CRAN (R 3.6.0)
 rlang         0.4.0   2019-06-25 [1] CRAN (R 3.6.0)
 rstudioapi    0.10    2019-03-19 [1] CRAN (R 3.6.0)
 sessioninfo   1.1.1   2018-11-05 [1] CRAN (R 3.6.0)
 SnowballC     0.6.0   2019-01-15 [1] CRAN (R 3.6.0)
 stringi       1.4.3   2019-03-12 [1] CRAN (R 3.6.0)
 stringr       1.4.0   2019-02-10 [1] CRAN (R 3.6.0)
 tibble        2.1.3   2019-06-06 [1] CRAN (R 3.6.0)
 tidyr       * 1.0.0   2019-09-11 [1] CRAN (R 3.6.1)
 tidyselect    0.2.5   2018-10-11 [1] CRAN (R 3.6.0)
 tidytext      0.2.2   2019-07-29 [1] CRAN (R 3.6.1)
 tokenizers    0.2.1   2018-03-29 [1] CRAN (R 3.6.0)
 utf8          1.1.4   2018-05-24 [1] CRAN (R 3.6.0)
 vctrs         0.2.0   2019-07-05 [1] CRAN (R 3.6.1)
 widyr       * 0.1.2   2019-09-09 [1] CRAN (R 3.6.1)
 withr         2.1.2   2018-03-15 [1] CRAN (R 3.6.0)
 zeallot       0.1.0   2018-01-28 [1] CRAN (R 3.6.0)

[TimBMK]

Any chance there's a solution to this yet? I'm running into the same problem with pairwise_pmi(); using pairwise_pmi_() doesn't help either. The calls work outside the function, but not when utilized inside a function. Specifically, when passing the arguments directly to pairwise_pmi_() via {{ var }} I'm getting:

`Error in (function (cl, name, valueClass)  : 
  assignment of an object of class “numeric” is not valid for @‘Dim’ in an object of class “dgTMatrix”; is(value, "integer") is not TRUE`

The same call outside of my function does work, however. Using the standard pairwise_pmi() call always results in
Error: Invalid column specification
no matter how I specify the colnames.

Any help appreciated!

[TimBMK]

Okay, I found the error. It was actually on my side, with the function producing erroneous dates to subset on, thus passing an empty dataframe to pairwise_pmi_.

So for anyone trying to pass columns with {{ embrace }} to functions like pairwise_pmi(), pairwise_cor() etc within a function or loop: Use the pairwise_cor_(), pairwise_pmi_() etc. functions. They can handle the {{ embrace }}. The "normal" function without the additional _ are just wrappers around them checking the column specifications, producing errors with {{ embrace }} (or with !!as.name() ).

[juliasilge]

Thanks for the info @TimBMK! I did some refactoring of how these functions use NSE a while back but still need to do more to be aligned with all the available ways to use rlang currently. In the meantime, your workaround looks good. 👍