Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
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linux
1// SPDX-License-Identifier: Apache-2.0 OR MIT
2
3#[cfg(feature = "parsing")]
4use crate::lookahead;
5
6pub use proc_macro2::Ident;
7
8#[cfg(feature = "parsing")]
9pub_if_not_doc! {
10 #[doc(hidden)]
11 #[allow(non_snake_case)]
12 pub fn Ident(marker: lookahead::TokenMarker) -> Ident {
13 match marker {}
14 }
15}
16
17macro_rules! ident_from_token {
18 ($token:ident) => {
19 impl From<Token![$token]> for Ident {
20 fn from(token: Token![$token]) -> Ident {
21 Ident::new(stringify!($token), token.span)
22 }
23 }
24 };
25}
26
27ident_from_token!(self);
28ident_from_token!(Self);
29ident_from_token!(super);
30ident_from_token!(crate);
31ident_from_token!(extern);
32
33impl From<Token![_]> for Ident {
34 fn from(token: Token![_]) -> Ident {
35 Ident::new("_", token.span)
36 }
37}
38
39pub(crate) fn xid_ok(symbol: &str) -> bool {
40 let mut chars = symbol.chars();
41 let first = chars.next().unwrap();
42 if !(first == '_' || first.is_ascii_alphabetic()) {
43 return false;
44 }
45 for ch in chars {
46 if !(ch == '_' || ch.is_ascii_alphanumeric()) {
47 return false;
48 }
49 }
50 true
51}
52
53#[cfg(feature = "parsing")]
54mod parsing {
55 use crate::buffer::Cursor;
56 use crate::error::Result;
57 use crate::parse::{Parse, ParseStream};
58 use crate::token::Token;
59 use proc_macro2::Ident;
60
61 fn accept_as_ident(ident: &Ident) -> bool {
62 match ident.to_string().as_str() {
63 "_" |
64 // Based on https://doc.rust-lang.org/1.65.0/reference/keywords.html
65 "abstract" | "as" | "async" | "await" | "become" | "box" | "break" |
66 "const" | "continue" | "crate" | "do" | "dyn" | "else" | "enum" |
67 "extern" | "false" | "final" | "fn" | "for" | "if" | "impl" | "in" |
68 "let" | "loop" | "macro" | "match" | "mod" | "move" | "mut" |
69 "override" | "priv" | "pub" | "ref" | "return" | "Self" | "self" |
70 "static" | "struct" | "super" | "trait" | "true" | "try" | "type" |
71 "typeof" | "unsafe" | "unsized" | "use" | "virtual" | "where" |
72 "while" | "yield" => false,
73 _ => true,
74 }
75 }
76
77 #[cfg_attr(docsrs, doc(cfg(feature = "parsing")))]
78 impl Parse for Ident {
79 fn parse(input: ParseStream) -> Result<Self> {
80 input.step(|cursor| {
81 if let Some((ident, rest)) = cursor.ident() {
82 if accept_as_ident(&ident) {
83 Ok((ident, rest))
84 } else {
85 Err(cursor.error(format_args!(
86 "expected identifier, found keyword `{}`",
87 ident,
88 )))
89 }
90 } else {
91 Err(cursor.error("expected identifier"))
92 }
93 })
94 }
95 }
96
97 impl Token for Ident {
98 fn peek(cursor: Cursor) -> bool {
99 if let Some((ident, _rest)) = cursor.ident() {
100 accept_as_ident(&ident)
101 } else {
102 false
103 }
104 }
105
106 fn display() -> &'static str {
107 "identifier"
108 }
109 }
110}