Rust doesn't support Emojis for variable names

[kparaju]

Rust currently doesn't support emojis for variable names. Is there any plans to include this feature?

➜  servo git:(mime-sniffing-one-sniffertask) ✗ ./mach build                                 
Compiling net v0.0.1 (file:///Users/kparaju/Documents/repos/servo)
resource_task.rs:224:13: 224:14 error: unknown start of token: \U0001f443
resource_task.rs:224         let 👃 = sniffer_task::new_sniffer_task();
                                 ^
Could not compile `net`.

[bstrie]

Sadly, at this time Rust only intends to support the subset of emotions that can be derived from UAX 31, and only then by employing a feature flag. You'll have to put some effort into your emoji, I'm afraid. For example:

#![feature(non_ascii_idents)]
#![allow(non_snake_case)]  // ㅋㅋㅋㅋ

fn main() {
    ಠ_ಠ();
}

fn ಠ_ಠ() {
    println!("Hello, 世界");
}

Post 1.0 I expect that we can consider expanding the definition of what is permitted within Unicode identifiers, though it would have to proceed through the RFC process.

[LenaWil]

Related RFC for those getting here through Google: #55467.

[Artoria2e5]

I am of the opinion that this issue should be reopened in light of the RFC being stabilized. As the friendly C++ folks noted on their report about adopting UAX #31 for C++:

6.3 Does not allow emoji

class \U0001F4A9 : public std::exception {};

Throwing “PILE OF POO” becomes ill-formed. Conference slide-ware will be less entertaining.

The same 💩 emoji is rejected by rust precisely due to UAX-31, and arguably it makes stuff less fun than what Swift allows :Q (On the other hand, it does render the point about emoji width calculation on the RFC moot!)

[flipbit03]

I don't see the issue with emoji or any unicode identifiers. It's just a code point after all.