core::ascii

Function escape_default

1.26.0 · source
pub fn escape_default(c: u8) -> EscapeDefault 
Expand description

Returns an iterator that produces an escaped version of a u8.

The default is chosen with a bias toward producing literals that are legal in a variety of languages, including C++11 and similar C-family languages. The exact rules are:

  • Tab is escaped as \t.
  • Carriage return is escaped as \r.
  • Line feed is escaped as \n.
  • Single quote is escaped as \'.
  • Double quote is escaped as \".
  • Backslash is escaped as \\.
  • Any character in the ‘printable ASCII’ range 0x20 .. 0x7e inclusive is not escaped.
  • Any other chars are given hex escapes of the form ‘\xNN’.
  • Unicode escapes are never generated by this function.

§Examples

use std::ascii;

let escaped = ascii::escape_default(b'0').next().unwrap();
assert_eq!(b'0', escaped);

let mut escaped = ascii::escape_default(b'\t');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b't', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'\r');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'r', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'\n');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'n', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'\'');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'\'', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'"');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'"', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'\\');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'\\', escaped.next().unwrap());

let mut escaped = ascii::escape_default(b'\x9d');

assert_eq!(b'\\', escaped.next().unwrap());
assert_eq!(b'x', escaped.next().unwrap());
assert_eq!(b'9', escaped.next().unwrap());
assert_eq!(b'd', escaped.next().unwrap());