use nom::{
bytes::complete::take_while,
IResult,
};
fn is_whitespace(input: char) -> bool {
input == ' ' || input == '\n' || input == '\t' || input == '\r'
}
/// Eat whitespace, returning it
pub fn eat_whitespace(input: &str) -> IResult<&str, &str> {
let (input, whitespace) = take_while(is_whitespace)(input)?;
Ok((input, whitespace))