blob: 8898d4c7d135222f184796eee45aa0dbb79d428a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
trait Document {
type Cursor<'a>: DocCursor<'a>;
//~^ ERROR: missing required bound on `Cursor`
fn cursor(&self) -> Self::Cursor<'_>;
}
struct DocumentImpl {}
impl Document for DocumentImpl {
type Cursor<'a> = DocCursorImpl<'a>;
fn cursor(&self) -> Self::Cursor<'_> {
DocCursorImpl { document: &self }
}
}
trait DocCursor<'a> {}
struct DocCursorImpl<'a> {
document: &'a DocumentImpl,
}
impl<'a> DocCursor<'a> for DocCursorImpl<'a> {}
struct Lexer<'d, Cursor>
where
Cursor: DocCursor<'d>,
{
cursor: Cursor,
_phantom: std::marker::PhantomData<&'d ()>,
}
impl<'d, Cursor> Lexer<'d, Cursor>
where
Cursor: DocCursor<'d>,
{
pub fn from<Doc>(document: &'d Doc) -> Lexer<'d, Cursor>
where
Doc: Document<Cursor<'d> = Cursor>,
{
Lexer { cursor: document.cursor(), _phantom: std::marker::PhantomData }
}
}
fn create_doc() -> impl Document<Cursor<'_> = DocCursorImpl<'_>> {
//~^ ERROR `'_` cannot be used here [E0637]
//~| ERROR: missing lifetime specifier
DocumentImpl {}
}
pub fn main() {
let doc = create_doc();
let lexer: Lexer<'_, DocCursorImpl<'_>> = Lexer::from(&doc);
}
|
