pub fn input_var(
input: &str,
vars: &[Variable],
sumrec: &mut Vec<(isize, String)>,
bracket: &mut isize,
options: Options,
print: bool,
depth: usize,
blacklist: Vec<char>,
isgraphing: bool,
collectvars: &mut Vec<(isize, usize)>,
solven: Option<usize>,
ison: Option<usize>,
) -> Result<(Vec<NumStr>, Vec<(String, Vec<NumStr>)>, HowGraphing, bool, Option<String>), &'static str>