Package 'ellipsis'

Check that dots are unused

Description

Sometimes you just want to use ... to force your users to fully name the details arguments. This function warns if ... is not empty.

Arguments

env	Environment in which to look for ....
action	The action to take when the dots have not been used. One of rlang::abort(), rlang::warn(), rlang::inform() or rlang::signal().

Examples

f <- function(x, ..., foofy = 8) {
  check_dots_empty()
  x + foofy
}

try(f(1, foof = 4))
f(1, foofy = 4)

---

Check that all dots are unnamed

Description

Named arguments in ... are often a sign of misspelled argument names.

Arguments

env	Environment in which to look for ....
action	The action to take when the dots have not been used. One of rlang::abort(), rlang::warn(), rlang::inform() or rlang::signal().

Examples

f <- function(..., foofy = 8) {
  check_dots_unnamed()
  c(...)
}

f(1, 2, 3, foofy = 4)
try(f(1, 2, 3, foof = 4))

---

Check that all dots have been used

Description

Automatically sets exit handler to run when function terminates, checking that all elements of ... have been evaluated. If you use on.exit() elsewhere in your function, make sure to use add = TRUE so that you don't override the handler set up by check_dots_used().

Arguments

env	Environment in which to look for ... and to set up handler.
action	The action to take when the dots have not been used. One of rlang::abort(), rlang::warn(), rlang::inform() or rlang::signal().

Examples

f <- function(...) {
  check_dots_used()
  g(...)
}

g <- function(x, y, ...) {
  x + y
}
f(x = 1, y = 2)

try(f(x = 1, y = 2, z = 3))
try(f(x = 1, y = 2, 3, 4, 5))

---

Safe version of median

Description

safe_median() works stats::median() but warns if some elements of ... are never used.

Usage

safe_median(x, ...)

## S3 method for class 'numeric'
safe_median(x, ..., na.rm = TRUE)

Arguments

x	Numeric vector
...	Additional arguments passed on to methods.
na.rm	For numeric method, should missing values be removed?

Examples

x <- c(1:10, NA)
safe_median(x, na.rm = TRUE)
median(x, na.rm = TRUE)

try(median(x, na.mr = TRUE))
try(safe_median(x, na.mr = TRUE))

try(median(1, 2, 3))
try(safe_median(1, 2, 3))

---