Function hex_append 

pub fn hex_append<'a>(src: &[u8], dst: &'a mut String) -> &'a mut str

Available on crate feature alloc only.

Appends lowercase hexadecimal digits to dst and returns the appended suffix.

Existing text is preserved, including non-ASCII text. The returned mutable string borrows only dst and contains exactly src.len() * 2 new ASCII digits. Empty input returns an empty suffix without changing the string.

Available with alloc. Existing capacity is reused without allocation when sufficient; otherwise the string grows. Call String::clear first to replace its contents while retaining the allocation. For a new string, use hex_string.

Panics

Panics if the resulting length cannot be represented or exceeds isize::MAX bytes. Allocation failure follows the allocator’s error handling.

Examples

use faster_hex::hex_append;

let mut text = String::with_capacity(64);
text.push_str("hash: ");
assert_eq!(hex_append(&[0xab, 0xcd], &mut text), "abcd");
assert_eq!(text, "hash: abcd");

text.clear();
hex_append(&[0, 1], &mut text);
assert_eq!(text, "0001");