Write a helper R script for a targets pipeline. Could be supporting functions or the target script file (default: _targets.R) itself.

tar_helper(path = NULL, code = NULL, tidy_eval = TRUE, envir = parent.frame())

Arguments

path

Character of length 1, path to write (or overwrite) code. If the parent directory does not exist, tar_helper_raw() creates it.

code

Quoted code to write to path. tar_helper() overwrites the file if it already exists.

tidy_eval

Logical, whether to use tidy evaluation on code. If turned on, you can substitute expressions and symbols using !! and !!!. See examples below.

envir

Environment for tidy evaluation.

Value

NULL (invisibly)

Details

tar_helper() is a specialized version of tar_script() with flexible paths and tidy evaluation.

See also

Examples

# Without tidy evaluation: path <- tempfile() tar_helper(path, x <- 1) writeLines(readLines(path))
#> x <- 1
# With tidy evaluation: y <- 123 tar_helper(path, x <- !!y) writeLines(readLines(path))
#> x <- 123