Generate a stop with a good error message if the dots argument was a non-trivial list. Useful in writing functions that force named arguments.

stop_if_dot_args(dot_args, msg = "")

Arguments

dot_args

substitute(list(...)) from another function.

msg

character, optional message to prepend.

Value

NULL or stop()

Examples

f <- function(x, ..., inc = 1) { stop_if_dot_args(substitute(list(...)), "f") x + inc } f(7)
#> [1] 8
f(7, inc = 2)
#> [1] 9
tryCatch( f(7, 2), error = function(e) { print(e) } )
#> <simpleError: f unexpected arguments: 2>