64 lines
1.7 KiB
Rust

pub fn spaces(size: u8) -> &'static str {
const SPACES: &str = " ";
&SPACES[..size as usize]
}
#[derive(Debug, Clone)]
pub struct Pos {
pub row: usize,
pub col: usize,
pub offset: usize,
}
impl Pos {
pub fn new(row: usize, col: usize, offset: usize) -> Self {
Self { row, col, offset }
}
}
#[derive(PartialEq, Eq, Clone, Copy)]
enum CharKind {
Space,
Punct,
Other,
}
impl CharKind {
fn new(c: char) -> Self {
if c.is_whitespace() {
Self::Space
} else if c.is_ascii_punctuation() {
Self::Punct
} else {
Self::Other
}
}
}
pub fn find_word_start_forward(line: &str, start_col: usize) -> Option<usize> {
let mut it = line.chars().enumerate().skip(start_col);
let mut prev = CharKind::new(it.next()?.1);
for (col, c) in it {
let cur = CharKind::new(c);
if cur != CharKind::Space && prev != cur {
return Some(col);
}
prev = cur;
}
None
}
pub fn find_word_start_backward(line: &str, start_col: usize) -> Option<usize> {
let idx = line.char_indices().nth(start_col).map(|(i, _)| i).unwrap_or(line.len());
let mut it = line[..idx].chars().rev().enumerate();
let mut cur = CharKind::new(it.next()?.1);
for (i, c) in it {
let next = CharKind::new(c);
if cur != CharKind::Space && next != cur {
return Some(start_col - i);
}
cur = next;
}
(cur != CharKind::Space).then_some(0)
}