R: Check that dots are empty

check_dots_empty {rlang}

R Documentation

Check that dots are empty

Description

... can be inserted in a function signature to force users to fully name the details arguments. In this case, supplying data in ... is almost always a programming error. This function checks that ... is empty and fails otherwise.

Usage

check_dots_empty(
  env = caller_env(),
  error = NULL,
  call = caller_env(),
  action = abort
)

Arguments

`env`	Environment in which to look for `...`.
`error`	An optional error handler passed to `try_fetch()`. Use this e.g. to demote an error into a warning.
`call`	The execution environment of a currently running function, e.g. `caller_env()`. The function will be mentioned in error messages as the source of the error. See the `call` argument of `abort()` for more information.
`action`

Details

In packages, document ... with this standard tag:

 @inheritParams rlang::args_dots_empty

Examples

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

# This fails because `foofy` can't be matched positionally
try(f(1, 4))

# This fails because `foofy` can't be matched partially by name
try(f(1, foof = 4))

# Thanks to `...`, it must be matched exactly
f(1, foofy = 4)

[Package rlang version 1.0.2 Index]