Unexpected Destructuring Behaviour

[KilianHanich]

Zig Version

0.12.0

Steps to Reproduce and Observed Behavior

const assert = @import("std").debug.assert;

test "swapping" {
    var x: u32 = 3;
    var y: u32 = 5;
    
    x, y = .{ y, x };
    
    assert(y == 3);
    assert(x == 5);
}

This fails, x and y are both 5.

Expected Behavior

The test does not fail or gives a compile error that swapping values this way (like in Python) doesn't work, even if the syntax suggests it.

[nektro]

Duplicate #12064

[nektro]

https://ziglang.org/documentation/master/std/#std.mem.swap is recommended for this use case

eg std.mem.swap(u32, &x, &y);

[KilianHanich]

Yeah ok, missed that issue.

[KilianHanich]

PS: While yes, std.mem.swap is better for this use case, I constructed a minimal example here. You should be able to use for this rotating multiple values (e.g. x, y, z = .{y, z, x};) too.