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#![allow(clippy::all)]
#![warn(clippy::pattern_type_mismatch)]
fn main() {}
fn syntax_match() {
let ref_value = &Some(&Some(42));
// not ok
match ref_value {
Some(_) => (),
None => (),
}
// ok
match ref_value {
&Some(_) => (),
&None => (),
}
match *ref_value {
Some(_) => (),
None => (),
}
}
fn syntax_if_let() {
let ref_value = &Some(42);
// not ok
if let Some(_) = ref_value {}
// ok
if let &Some(_) = ref_value {}
if let Some(_) = *ref_value {}
}
fn syntax_while_let() {
let ref_value = &Some(42);
// not ok
while let Some(_) = ref_value {
break;
}
// ok
while let &Some(_) = ref_value {
break;
}
while let Some(_) = *ref_value {
break;
}
}
fn syntax_for() {
let ref_value = &Some(23);
let slice = &[(2, 3), (4, 2)];
// not ok
for (_a, _b) in slice.iter() {}
// ok
for &(_a, _b) in slice.iter() {}
}
fn syntax_let() {
let ref_value = &(2, 3);
// not ok
let (_n, _m) = ref_value;
// ok
let &(_n, _m) = ref_value;
let (_n, _m) = *ref_value;
}
fn syntax_fn() {
// not ok
fn foo((_a, _b): &(i32, i32)) {}
// ok
fn foo_ok_1(&(_a, _b): &(i32, i32)) {}
}
fn syntax_closure() {
fn foo<F>(f: F)
where
F: FnOnce(&(i32, i32)),
{
}
// not ok
foo(|(_a, _b)| ());
// ok
foo(|&(_a, _b)| ());
}
fn macro_with_expression() {
macro_rules! matching_macro {
($e:expr) => {
$e
};
}
let value = &Some(23);
// not ok
matching_macro!(match value {
Some(_) => (),
_ => (),
});
// ok
matching_macro!(match value {
&Some(_) => (),
_ => (),
});
matching_macro!(match *value {
Some(_) => (),
_ => (),
});
}
fn macro_expansion() {
macro_rules! matching_macro {
($e:expr) => {
// not ok
match $e {
Some(_) => (),
_ => (),
}
// ok
match $e {
&Some(_) => (),
_ => (),
}
match *$e {
Some(_) => (),
_ => (),
}
};
}
let value = &Some(23);
matching_macro!(value);
}
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