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//! Tests how we behave when the user attempts to mutate an immutable
//! binding that was introduced by either `ref` or `ref mut`
//! patterns.
//!
//! Such bindings cannot be made mutable via the mere addition of the
//! `mut` keyword, and thus we want to check that the compiler does not
//! suggest doing so.
fn main() {
let (mut one_two, mut three_four) = ((1, 2), (3, 4));
// Bind via pattern:
// - `a` as immutable reference (`ref`)
// - `b` as mutable reference (`ref mut`)
let &mut (ref a, ref mut b) = &mut one_two;
// Attempt to reassign immutable `ref`-bound variable
a = &three_four.0;
//~^ ERROR cannot assign twice to immutable variable `a`
// Attempt to reassign mutable `ref mut`-bound variable
b = &mut three_four.1;
//~^ ERROR cannot assign twice to immutable variable `b`
}
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