Macro zstr::zstr

zstr!() { /* proc-macro */ }

Given a Rust string or byte string literal, this macro generates an expression of type &'static CStr that is properly 0-terminated and ensured not to contain any internal NUL (0) bytes. The conversion is zero-cost and it may even become const in the future, provided that CStr::from_bytes_with_nul_unchecked() becomes const.

Examples:

use zstr::zstr;

// Works with Unicode characters and escapes in Rust strings
let c_str_1 = zstr!("Hello 🎉");
assert_eq!(c_str_1.to_bytes(), b"Hello \xf0\x9f\x8e\x89");
assert_eq!(c_str_1.to_bytes_with_nul(), b"Hello \xf0\x9f\x8e\x89\x00");

let c_str_2 = zstr!("Hello \u{1F389}");
assert_eq!(c_str_1, c_str_2);

let c_str_3 = zstr!(b"hello\x20ASCII");
assert_eq!(c_str_3.to_bytes(), b"hello ASCII");
assert_eq!(c_str_3.to_bytes_with_nul(), b"hello ASCII\x00");

Strings with embedded NUL (zero) bytes are not allowed:

let invalid_1 = zstr!("null here: \x00 is forbidden");
let invalid_2 = zstr!("also at the end: \0");
let invalid_3 = zstr!(b"and in byte \x00 strings too");