syntax: Extra diagnostics for _ used in an identifier position
#32506
Conversation
|
r? @pnkfelix (rust_highfive has picked a reviewer for you, use r? to override) |
| let mut err = self.fatal(&format!("expected identifier, found `{}`", | ||
| self.this_token_to_string())); | ||
| if self.token == token::Underscore { | ||
| err.fileline_note(self.span, "`_` is not an identifier but a wildcard pattern \ |
There was a problem hiding this comment.
According to the reference, a "wildcard pattern" is .. (two dots) which can match with multiple data fields, as in
struct S(i32, i32);
let S(..) = S(0, 1);The underscore seems to be called a "placeholder".
There was a problem hiding this comment.
I don't know, the compiler uses "wildcard", wikipedia uses it too and that part of the reference looks ancient and not well-maintained.
|
👍 while the referenced issue is a bit artificial, people are regularly confused by |
|
r? @Manishearth |
| let mut err = self.fatal(&format!("expected identifier, found `{}`", | ||
| self.this_token_to_string())); | ||
| if self.token == token::Underscore { | ||
| err.fileline_note(self.span, "`_` is a wildcard pattern and not an identifier"); |
There was a problem hiding this comment.
nit: "pattern, not an" instead of "pattern and not an"
|
@bors delegate+ r=me once you fix the nit. (comment |
|
📌 Commit 1c08cb1 has been approved by `Manishearth`` |
|
✌️ @petrochenkov can now approve this pull request |
|
@bors r- ugh, it picked up the r=manishearth from my comment |
|
@bors r=Manishearth |
|
📌 Commit 1cbdf4e has been approved by |
syntax: Extra diagnostics for `_` used in an identifier position Closes #32501
Closes #32501