Description
Code
fn bar() {
'🐱 loop {
break
}
}Current output
error[E0762]: unterminated character literal
--> src/lib.rs:2:5
|
2 | '🐱 loop {
| ^^^^^^^^^^Desired output
error: identifiers cannot contain emoji
--> src/lib.rs:2:5
|
2 | '🐱: loop {
| ^^or something else similar to the one for
fn bar() {
let 🐱 = ();
}
error: identifiers cannot contain emoji: `🐱`
--> src/lib.rs:2:9
|
2 | let 🐱 = ();
| ^^
Perhaps with a =help "did you mean to use a character literal?" when applicable
Rationale and extra context
I feel the rationale is self-explanatory, however, if it ends up not being such, I can provide one upon request.
Other cases
small aside: I originally wrote this all for 🥺, but that is bizarrely not recognized in idents at all (it gives a error: unknown start of token: \u{1f97a}), and after realizing that some emotes are handled better, I decided to use to use 🐱. I specifically avoided 🦀 because it has extra-special handling ("Ferris cannot be used as an identifier")
Another case is, as mentioned prior, in lifetime names (as far as I'm aware, this is the same underlying cause: the emoji causes the token to be a character literal):
fn foo<'🐱>() -> &'🐱 () {
&()
}which gives 2 errors:
error: character literal may only contain one codepoint
--> src/lib.rs:1:8
|
1 | fn foo<'🐱>() -> &'🐱 () {
| ^^^^^^^^^^^^
|
help: if you meant to write a `str` literal, use double quotes
|
1 | fn foo<"🐱>() -> &"🐱 () {
| ~~~~~~~~~~~~
error: expected one of `#`, `>`, `const`, identifier, or lifetime, found `'🐱>() -> &'`
--> src/lib.rs:1:8
|
1 | fn foo<'🐱>() -> &'🐱 () {
| ^^^^^^^^^^^^ expected one of `#`, `>`, `const`, identifier, or lifetime
The following sample also has very different output (and probably closer to the expected output, although it's not without its own weirdness):
fn bar() {
'a🐱: loop {}
}
error: malformed loop label
--> src/lib.rs:6:7
|
6 | 'a🐱: loop {}
| ^^ help: use the correct loop label format: `'🐱`
error: expected `while`, `for`, `loop` or `{` after a label
--> src/lib.rs:6:7
|
6 | 'a🐱: loop {}
| ^^ expected `while`, `for`, `loop` or `{` after a label
|
help: consider removing the label
|
6 - 'a🐱: loop {}
6 + 🐱: loop {}
|
error: labeled expression must be followed by `:`
--> src/lib.rs:6:7
|
6 | 'a🐱: loop {}
| ---^^^^^^^^^^
| | |
| | help: add `:` after the label
| the label
|
= note: labels are used before loops and blocks, allowing e.g., `break 'label` to them
error: identifiers cannot contain emoji: `🐱`
--> src/lib.rs:6:7
|
6 | 'a🐱: loop {}
| ^^
warning: unused label
--> src/lib.rs:6:7
|
6 | 'a🐱: loop {}
| ^^
|
= note: `#[warn(unused_labels)]` on by default
warning: `playground` (lib) generated 1 warning
error: could not compile `playground` due to 4 previous errors; 1 warning emitted
Anything else?
No response