drake (version 5.0.0)

drake_plan: Create a workflow plan data frame for the plan argument of make.

Description

Turns a named collection of target/command pairs into a workflow plan data frame for make() and check(). You can give the commands as named expressions, or you can use the list argument to supply them as character strings.

Usage

drake_plan(..., list = character(0), file_targets = FALSE,
  strings_in_dots = c("filenames", "literals"))

Arguments

...

A collection of symbols/targets with commands assigned to them. See the examples for details.

list

A named list of targets, where the values are commands.

file_targets

logical, whether the targets should be (single-quoted) external file targets.

strings_in_dots

Character scalar, how to treat quoted character strings in the commands specified through .... Set to "filenames" to treat all these strings as external file targets/imports (single-quoted), or to "literals" to treat them all as literal strings (double-quoted). Unfortunately, because of how R deparses code, you cannot simply leave literal quotes alone in the ... argument. R will either convert all these quotes to single quotes or double quotes. Literal quotes in the list argument are left alone.

Value

A data frame of targets and commands.

Details

A workflow plan data frame is a data frame with a target column and a command column. Targets are the objects and files that drake generates, and commands are the pieces of R code that produce them.

For file inputs and targets, drake uses single quotes. Double quotes are reserved for ordinary strings. The distinction is important because drake thinks about how files, objects, targets, etc. depend on each other. Quotes in the list argument are left alone, but R messes with quotes when it parses the free-form arguments in ..., so use the strings_in_dots argument to control the quoting in ....

Examples

# NOT RUN {
# Create example workflow plan data frames for make()
drake_plan(small = simulate(5), large = simulate(50))
# Commands can be multi-line code chunks.
small_plan <- drake_plan(
  small_target = {
    local_object <- 1 + 1
    2 + sqrt(local_object)
  }
)
small_plan
# }
# NOT RUN {
make(small_plan)
cached()
readd(small_target)
# local_object only applies to the code chunk.
ls() # your environment is protected (local_object not found)
# }
# NOT RUN {
# For tighter control over commands, use the `list` argument.
drake_plan(list = c(x = "1 + 1", y = "sqrt(x)"))
# This becomes important for file targets,
# which you must put in single quotes.
# (Double quotes are for string literals.)
drake_plan(data = readRDS("my_data.rds"))
drake_plan(my_file.rds = saveRDS(1+1, "my_file.rds"), file_targets = TRUE,
  strings_in_dots = "literals")
# }