Function take_some_while_until

pub fn take_some_while_until<I, T, F>(
    input: &mut Pear<I>,
    cond: F,
    until: T,
) -> Result<I::Many, I>
where
    I: Input,
    T: Token<I>,
    F: FnMut(&I::Token) -> bool,

Consumes tokens while cond matches and the token is not until. Succeeds only if at least one token matched cond.