RustCrypto: hex-literal
This crate provides the hex! macro for converting hexadecimal string literals to a byte array at compile time.
It accepts the following characters in the input string:
'0'...'9','a'...'f','A'...'F'— hex characters which will be used in construction of the output byte array' ','\r','\n','\t'— formatting characters which will be ignored
use hex_literal::hex;
// The macro can be used in const contexts
const DATA: [u8; 4] = hex!("01020304");
assert_eq!(DATA, [1, 2, 3, 4]);
// Both upper and lower hex values are supported
assert_eq!(hex!("a1 b2 c3 d4"), [0xA1, 0xB2, 0xC3, 0xD4]);
assert_eq!(hex!("E5 E6 90 92"), [0xE5, 0xE6, 0x90, 0x92]);
assert_eq!(hex!("0a0B 0C0d"), [10, 11, 12, 13]);
// Multi-line literals
let bytes1 = hex!("
00010203 04050607
08090a0b 0c0d0e0f
");
assert_eq!(
bytes1,
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15],
);
// It's possible to use several literals
// (results will be concatenated)
let bytes2 = hex!(
"00010203 04050607" // first half
"08090a0b 0c0d0e0f" // second half
);
assert_eq!(bytes1, bytes2);Using an unsupported character inside literals will result in a compilation error:
hex_literal::hex!("АА"); // Cyrillic "А"
hex_literal::hex!("11 22"); // Japanese spaceСomments inside literals are not supported:
hex_literal::hex!("0123 // foo");Each literal must contain an even number of hex characters:
hex_literal::hex!(
"01234"
"567"
);Rust 1.57 or newer.
In the future, we reserve the right to change MSRV (i.e. MSRV is out-of-scope for this crate's SemVer guarantees), however when we do it will be accompanied by a minor version bump.
Licensed under either of:
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.