Zig's comptime for Rust, with zero dependencies.
cargo add constimeDependencies in comptime! can be stored in either [dependencies] or [build-dependencies], and must be explicitly imported using extern crate.
You will also need a build.rs file in order to force [build-dependencies] to compile.
fn main() {
use constime::comptime;
// Let's use a pure-build time dependency
println!("Here's a fact about the number 5: {}", comptime! {
extern crate ureq;
ureq::get("http://numbersapi.com/5/math").call().unwrap().into_string().unwrap()
});
// Standard library works fine too.
println!(
"Compiled {} seconds after unix epoch.",
comptime! {
std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.expect("Time went backwards")
.as_secs()
}
);
}