https://github.com/dvvcz/constime

Zig's comptime for Rust. Allows you to incorporate side effects into your `const` code.
https://github.com/dvvcz/constime

compile-time comptime macro metaprogramming proc-macro rust

Last synced: 6 days ago
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Zig's comptime for Rust. Allows you to incorporate side effects into your `const` code.

• Host: GitHub
• URL: https://github.com/dvvcz/constime
• Owner: DvvCz
• License: mit
• Created: 2023-01-06T04:42:41.000Z (almost 2 years ago)
• Default Branch: master
• Last Pushed: 2024-04-22T01:06:58.000Z (7 months ago)
• Last Synced: 2024-10-07T23:07:42.187Z (about 1 month ago)
• Topics: compile-time, comptime, macro, metaprogramming, proc-macro, rust
• Language: Rust
• Homepage: https://docs.rs/constime
• Size: 9.77 KB
• Stars: 10
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
 constime 




	Zig's comptime for Rust, with zero dependencies.





	

		

	

	

		

	

	

		

	



## Usage

```bash

cargo add constime

```

Dependencies 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.

## Example

```rust

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()

		}

	);

}

```