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#[warn(clippy::mixed_read_write_in_expression)]
#[allow(
unused_assignments,
unused_variables,
clippy::no_effect,
dead_code,
clippy::disallowed_names
)]
fn main() {
let mut x = 0;
let a = {
x = 1;
1
} + x;
// Example from iss#277
x += {
x = 20;
2
};
// Does it work in weird places?
// ...in the base for a struct expression?
struct Foo {
a: i32,
b: i32,
};
let base = Foo { a: 4, b: 5 };
let foo = Foo {
a: x,
..{
x = 6;
base
}
};
// ...inside a closure?
let closure = || {
let mut x = 0;
x += {
x = 20;
2
};
};
// ...not across a closure?
let mut y = 0;
let b = (y, || y = 1);
// && and || evaluate left-to-right.
let a = {
x = 1;
true
} && (x == 3);
let a = {
x = 1;
true
} || (x == 3);
// Make sure we don't get confused by alpha conversion.
let a = {
let mut x = 1;
x = 2;
1
} + x;
// No warning if we don't read the variable...
x = {
x = 20;
2
};
// ...if the assignment is in a closure...
let b = {
|| {
x = 1;
};
1
} + x;
// ... or the access is under an address.
let b = (
{
let p = &x;
1
},
{
x = 1;
x
},
);
// Limitation: l-values other than simple variables don't trigger
// the warning.
let mut tup = (0, 0);
let c = {
tup.0 = 1;
1
} + tup.0;
// Limitation: you can get away with a read under address-of.
let mut z = 0;
let b = (
&{
z = x;
x
},
{
x = 3;
x
},
);
}
async fn issue_6925() {
let _ = vec![async { true }.await, async { false }.await];
}
|
