/// Otherwise, the span reached to limit is returned.
pub fn span_look_ahead(&self, span: Span, expect: Option<&str>, limit: Option<usize>) -> Span {
let mut sp = span;
/// Otherwise, the span reached to limit is returned.
pub fn span_look_ahead(&self, span: Span, expect: Option<&str>, limit: Option<usize>) -> Span {
let mut sp = span;