ignore {drake}R Documentation

Ignore code [Stable]

Description

Ignore sections of commands and imported functions.

Usage

ignore(x = NULL)

Arguments

x

Code to ignore.

Details

In user-defined functions and drake_plan() commands, you can wrap code chunks in ignore() to

  1. Tell drake to not search for dependencies (targets etc. mentioned in the code) and

  2. Ignore changes to the code so downstream targets remain up to date. To enforce (1) without (2), use no_deps().

Value

The argument.

Keywords

drake_plan() understands special keyword functions for your commands. With the exception of target(), each one is a proper function with its own help file.

See Also

file_in(), file_out(), knitr_in(), no_deps()

Examples

## Not run: 
isolate_example("Contain side effects", {
# Normally, `drake` reacts to changes in dependencies.
x <- 4
make(plan = drake_plan(y = sqrt(x)))
x <- 5
make(plan = drake_plan(y = sqrt(x)))
make(plan = drake_plan(y = sqrt(4) + x))
# But not with ignore().
make(plan = drake_plan(y = sqrt(4) + ignore(x))) # Builds y.
x <- 6
make(plan = drake_plan(y = sqrt(4) + ignore(x))) # Skips y.
make(plan = drake_plan(y = sqrt(4) + ignore(x + 1))) # Skips y.

# ignore() works with functions and multiline code chunks.
f <- function(x) {
  ignore({
    x <- x + 1
    x <- x + 2
  })
  x # Not ignored.
}
make(plan = drake_plan(y = f(2)))
readd(x)
# Changes the content of the ignore() block:
f <- function(x) {
  ignore({
    x <- x + 1
  })
  x # Not ignored.
}
make(plan = drake_plan(x = f(2)))
readd(x)
})

## End(Not run)

[Package drake version 7.13.2 Index]