Check that argument is supplied Throws an informative error if arg is missing.

arg_require(arg, error_arg = caller_arg(arg), error_call = caller_env())

## Arguments

arg A function argument. Must be a symbol. An argument name as a string. This argument will be mentioned in error messages as the input that is at the origin of a problem. 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.

arg_match()

## Examples

f <- function(x)  {
arg_require(x)
}

# Fails because x is not supplied
try(f())
#> Error in f() :
#>   x must be supplied.
# Succeeds
f(NULL)
#> [1] TRUE