What output do you think this has, and what do you think it should have / wish it had?

[kj4tmp]

From a language specification consistency and understandability standpoint, I definitely think the execution ordering is much better than a special-casing rule to perform the swapping “all at once”.

Semi-related topic on importance of order in struct initialization:

Do struct field initializations occur in well defined order?

Are the fields in the following struct guaranteed to initialize in a specific order (will the reader always read dest_mac, src_mac, then ether_type? const ethernet_header = telegram.EthernetHeader{ .dest_mac = try reader.readInt(u48, big), .src_mac = try reader.readInt(u48, big), .ether_type = try reader.readInt(u16, big), };