nac3/nac3ast/src/location.rs

80 lines
1.7 KiB
Rust

//! Datatypes to support source location information.
use std::fmt;
/// A location somewhere in the sourcecode.
#[derive(Clone, Copy, Debug, Default, PartialEq)]
pub struct Location {
row: usize,
column: usize,
}
impl fmt::Display for Location {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "line {} column {}", self.row, self.column)
}
}
impl Location {
pub fn visualize<'a>(
&self,
line: &'a str,
desc: impl fmt::Display + 'a,
) -> impl fmt::Display + 'a {
struct Visualize<'a, D: fmt::Display> {
loc: Location,
line: &'a str,
desc: D,
}
impl<D: fmt::Display> fmt::Display for Visualize<'_, D> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(
f,
"{}\n{}\n{arrow:>pad$}",
self.desc,
self.line,
pad = self.loc.column,
arrow = "",
)
}
}
Visualize {
loc: *self,
line,
desc,
}
}
}
impl Location {
pub fn new(row: usize, column: usize) -> Self {
Location { row, column }
}
pub fn row(&self) -> usize {
self.row
}
pub fn column(&self) -> usize {
self.column
}
pub fn reset(&mut self) {
self.row = 1;
self.column = 1;
}
pub fn go_right(&mut self) {
self.column += 1;
}
pub fn go_left(&mut self) {
self.column -= 1;
}
pub fn newline(&mut self) {
self.row += 1;
self.column = 1;
}
}