refactor(clog): update to beta compatible version of Rust

[kbknapp]

Allows compiling with stable Rust 1.0 beta channel (i.e. nightly not required)

[vyp]

This is not related, but on #16, you said

I can confirm that it does, that's what I've been using for a while now ;)

So does that mean you are on Arch Linux too? Because how did you get Rust beta, did you find a package, or did you build it yourself? (Because the official package is still outdated.)

I'm using the nightly as usual for the moment (which compiles this pr btw).

[kbknapp]

@vyp yep, I use Arch. For Rust I use multirust so I can develop against both stable and nightly at the same time, but you can also just use the regular rustup.sh to install either the beta or nightly (assuming you only want one). Before the beta was out, I used the AUR rust-nightly-bin package.

For Beta:
$ curl -s https://static.rust-lang.org/rustup.sh | sudo sh

For Nightly:
$ curl -s https://static.rust-lang.org/rustup.sh | sudo sh -s -- --channel=nightly

The AUR should hopefully get the beta soon. If not, I'm sure the official arch repos will get stable 1.0 once released.

[cburgdorf]

THANKS! Would still love to get my question addressed just for the purpose of learning :)

[kbknapp]

@cburgdorf It's because syntax extensions aren't supported in stable/beta (since they're unstable), only procedural macros are allowed. Procedural macros can't be at the top level (i.e. static) when they require a function call (perhaps not all?). So we end up paying a [very small] performance hit because the regex is recompiled each time, but it's so small it's not noticeable (talking ns/ms slower). Once syntax extensions are stable we should be able to re-incorporate the real regex! macro back at the static level.

[cburgdorf]

Understood! Thanks for clarifying :)

[kbknapp]

No problem :)

[vyp]

Oh cool, multirust looks really great. Thanks for the info!