auto merge of #8857 : blake2-ppc/rust/std-str-remove, r=thestinger

These are very easy to replace with methods on string slices, basically
`.char_len()` and `.len()`.

These are the replacement implementations I did to clean these
functions up, but seeing this I propose removal:

/// ...
pub fn count_chars(s: &str, begin: uint, end: uint) -> uint {
    // .slice() checks the char boundaries
    s.slice(begin, end).char_len()
}

/// Counts the number of bytes taken by the first `n` chars in `s`
/// starting from byte index `begin`.
///
/// Fails if there are less than `n` chars past `begin`
pub fn count_bytes<'b>(s: &'b str, begin: uint, n: uint) -> uint {
    s.slice_from(begin).slice_chars(0, n).len()
}
This commit is contained in:
bors 2013-08-30 04:40:47 -07:00
commit 1f9bd62fd6

View File

@ -907,46 +907,6 @@ pub fn with_capacity(capacity: uint) -> ~str {
}
}
/// As char_len but for a slice of a string
///
/// # Arguments
///
/// * s - A valid string
/// * start - The position inside `s` where to start counting in bytes
/// * end - The position where to stop counting
///
/// # Return value
///
/// The number of Unicode characters in `s` between the given indices.
pub fn count_chars(s: &str, start: uint, end: uint) -> uint {
assert!(s.is_char_boundary(start));
assert!(s.is_char_boundary(end));
let mut i = start;
let mut len = 0u;
while i < end {
let next = s.char_range_at(i).next;
len += 1u;
i = next;
}
return len;
}
/// Counts the number of bytes taken by the first `n` chars in `s`
/// starting from `start`.
pub fn count_bytes<'b>(s: &'b str, start: uint, n: uint) -> uint {
assert!(s.is_char_boundary(start));
let mut end = start;
let mut cnt = n;
let l = s.len();
while cnt > 0u {
assert!(end < l);
let next = s.char_range_at(end).next;
cnt -= 1u;
end = next;
}
end - start
}
// https://tools.ietf.org/html/rfc3629
static UTF8_CHAR_WIDTH: [u8, ..256] = [
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,