I'm creating a workflow that contains the same piping steps of renaming, selecting by, then mutating all using a name I provide prior to the pipe.
I have had success using enquo() and !!(bang bang) to rename to my desired string and then select it again, but when I reach the mutate step it either repeats the text string as the column values or will not evaluate.
I've recreated the code below:
#Testing rename, select, and mutate use cases for enquo()
#Load packages
library(dplyr)
library(rlang)
library(magrittr)
#Create name I want to pass
new_var <- quo("new_name")
#Create Test Data
t1 <- tibble(Year = c(2000:2004),
old_name = c(NA, 1, 1, 1, NA))
I can rename the column with quo_name() and :=
t1 %>%
rename( !! quo_name(new_var) := old_name)
I can select on it using !!
t1 %>%
rename( !! quo_name(new_var) := old_name) %>%
select(Year, !!new_var)
But I can't then call that column in mutate and use the values
t1 %>%
rename( !! quo_name(new_var) := old_name) %>%
select(Year, !!new_var) %>%
mutate(test_var = (!! new_var))
The 'new_var' object is a quosure on a string. Extract the string, convert it to symbol and then do the evaluation
t1 %>%
rename( !! quo_name(new_var) := old_name) %>%
select(Year, !!new_var) %>%
mutate(testvar = !! rlang::sym(rlang::quo_name(new_var)))
# A tibble: 5 x 3
# Year new_name testvar
# <int> <dbl> <dbl>
#1 2000 NA NA
#2 2001 1 1
#3 2002 1 1
#4 2003 1 1
#5 2004 NA NA
Also, if we start with unquoted the new_var in quosure, then the OP's code works
new_var = quo(new_name)
t1 %>%
rename(!! new_var := old_name) %>%
select(Year, !!new_var) %>%
mutate(testvar = !! new_var)
# A tibble: 5 x 3
# Year new_name testvar
# <int> <dbl> <dbl>
#1 2000 NA NA
#2 2001 1 1
#3 2002 1 1
#4 2003 1 1
#5 2004 NA NA