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pub fn is_boundary(line: &str, ix: Option<usize>) -> bool {
ix.and_then(|v| line.chars().nth(v))
.map(|c| c.is_whitespace() || c == '"' || c == '(' || c == ')' || c == '<' || c == '>')
.unwrap_or(true)
}
pub fn find_from(line: &str, ix_start: usize, key: &str) -> Option<usize> {
line[ix_start..].find(key).map(|v| ix_start + v)
}
pub fn find_from_u8(line: &[u8], ix_start: usize, key: &[u8]) -> Option<usize> {
assert!(!key.is_empty());
assert!(ix_start < line.len());
if line.len() < key.len() {
return None;
}
let ix_end = line.len() - key.len();
if ix_start <= ix_end {
for i in ix_start..ix_end {
if line[i] == key[0] {
let mut success = true;
for j in 1..key.len() {
if line[i + j] != key[j] {
success = false;
break;
}
}
if success {
return Some(i);
}
}
}
}
None
}
#[test]
fn test_find_from_u8() {
assert_eq!(find_from_u8(b"hello world", 0, b"hell"), Some(0));
assert_eq!(find_from_u8(b"hello world", 0, b"o"), Some(4));
assert_eq!(find_from_u8(b"hello world", 4, b"o"), Some(4));
assert_eq!(find_from_u8(b"hello world", 5, b"o"), Some(7));
assert_eq!(find_from_u8(b"hello world", 8, b"o"), None);
assert_eq!(find_from_u8(b"hello world", 10, b"d"), None);
}
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