Do the prework in the prework argument to make().

For internal use only. The only reason this function is exported is to set up parallel socket (PSOCK) clusters without too much fuss.

Usage

do_prework(config, verbose_packages)

Arguments

config

A configured workflow from drake_config().

verbose_packages

logical, whether to print package startup messages

Value

Inivisibly returns NULL.

Examples

if (FALSE) { # \dontrun{
isolate_example("Quarantine side effects.", {
if (suppressWarnings(require("knitr"))) {
load_mtcars_example() # Get the code with drake_example("mtcars").
# Create a main internal configuration list with prework.
con <- drake_config(my_plan, prework = c("library(knitr)", "x <- 1"))
# Do the prework. Usually done at the beginning of `make()`,
# and for distributed computing backends like "future_lapply",
# right before each target is built.
do_prework(config = con, verbose_packages = TRUE)
# The `eval` element is the environment where the prework
# and the commands in your workflow plan data frame are executed.
identical(con$eval$x, 1) # Should be TRUE.
}
})
} # }