x is atomic and single valued (has length 1)

Check that value x is atomic and single valued (has length 1)

assert_single(
  x,
  message = "%s must be a single value",
  name = deparse(substitute(x))
)

Arguments

x	Value to check if atomic and single valued (has length 1)
message	Message to output if x not atomic and single valued
name	Name

Details

Check that x is atomic and single valued (has length 1)