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Dewey Dunnington commented on ARROW-13858: ------------------------------------------ Just doing some exploring: Where the field reference is created in from /R: https://github.com/apache/arrow/blob/master/r/R/expression.R#L170-L173 Where the field reference is created in /src: https://github.com/apache/arrow/blob/master/r/src/expression.cpp#L72-L74 Example of creating a nested field reference from a test (but it appears it wasn't implemented?) https://github.com/lidavidm/arrow/blob/master/cpp/src/arrow/compute/exec/expression_test.cc#L506-L509 You can do this kind of thing in dplyr using {{$}}: {code:R} library(arrow, warn.conflicts = FALSE) library(dplyr, warn.conflicts = FALSE) RecordBatch$create(df_col = tibble(a = 1)) %>% mutate(df_col_a = df_col$a) %>% collect() #> # A tibble: 1 × 1 #> df_col$a #> <dbl> #> 1 1 tibble(df_col = tibble(a = 1)) %>% mutate(df_col_a = df_col$a) #> # A tibble: 1 × 2 #> df_col$a df_col_a #> <dbl> <dbl> #> 1 1 1 {code} > [R] Create a field ref to a field in a struct > --------------------------------------------- > > Key: ARROW-13858 > URL: https://issues.apache.org/jira/browse/ARROW-13858 > Project: Apache Arrow > Issue Type: Improvement > Components: R > Reporter: Neal Richardson > Priority: Major > Labels: query-engine > Fix For: 7.0.0 > > > See also ARROW-11259. This probably needs to be a {{$}} and {{[[}} method on > {{Expression}} -- This message was sent by Atlassian Jira (v8.20.1#820001)