Macro span 

macro_rules! span {
    ($line_start:expr, $col_start:expr, $line_end:expr, $col_end:expr) => { ... };
}

Build an Span inline from 0-based line/column coordinates.

This macro returns Span { ... }, which is convenient for populating fields like ParlexError { span, .. }.

Examples

let s = span!(0, 0, 1, 4);
assert_eq!(s.unwrap().end.column, 4);