[std::concat!] with support for const variables and expressions.
Works on stable Rust ✨.
Add constcat to your Cargo manifest.
sh
cargo add constcat
Import the macro using the following.
rust
use constcat::concat;
concat! works exactly like [std::concat!] except you can
now pass variables and constant expressions. For example:
rust
const CRATE_NAME: &str = env!("CARGO_PKG_NAME");
const CRATE_VERSION: &str = env!("CARGO_PKG_VERSION");
const fn tada() -> &'static str { "🎉" }
const VERSION: &str = concat!(CRATE_NAME, " ", CRATE_VERSION, tada());
concat_bytes! works similarly except it yields a static byte slice. For
example:
rust
const VERSION: u32 = 1;
const fn entries() -> &'static [u8] { b"example" }
const HEADER: &[u8] = concat_bytes!(&VERSION.to_le_bytes(), entries());
This project is distributed under the terms of both the MIT license and the Apache License (Version 2.0).
See LICENSE-APACHE and LICENSE-MIT for details.