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#![feature(if_let_guard)]
enum Enum<'a> {
A(&'a isize),
B(bool),
}
fn if_guard() -> isize {
let mut n = 42;
let mut x = Enum::A(&mut n);
match x {
Enum::A(_) if { x = Enum::B(false); false } => 1,
//~^ ERROR cannot assign `x` in match guard
Enum::A(_) if { let y = &mut x; *y = Enum::B(false); false } => 1,
//~^ ERROR cannot mutably borrow `x` in match guard
Enum::A(p) => *p,
Enum::B(_) => 2,
}
}
fn if_let_guard() -> isize {
let mut n = 42;
let mut x = Enum::A(&mut n);
match x {
Enum::A(_) if let Some(()) = { x = Enum::B(false); None } => 1,
//~^ ERROR cannot assign `x` in match guard
Enum::A(_) if let Some(()) = { let y = &mut x; *y = Enum::B(false); None } => 1,
//~^ ERROR cannot mutably borrow `x` in match guard
Enum::A(p) => *p,
Enum::B(_) => 2,
}
}
fn main() {}
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