When a structure calls a method that requires `self` to be a pointer, the parameter is automatically and implicitly converted to a pointer. Are there any irreplaceable uses for this?

[rpkak]

some related links:

Zig 0.15.1 reader/writer: Don't make copies of @fieldParentPtr()-based interfaces

Here is a dedicated write-up for those not familiar with @fieldParentPtr-based interfaces, which is how the new reader/writer interface is implemented. These two programs produce drastically different results: bad_program.zig: const std = @import("std"); pub fn main() !void { const my_struct: struct { hello: []const u8 } = .{ .hello = "world" }; var buffer: [1024]u8 = undefined; var file_writer = std.fs.File.stdout().writer(&buffer); var writer_instance = file_writer.interfa…

Struct method reference to `self` by pointer or not?

Kinda a basic question but a little context: I’m parsing a UDP packet as a struct called Packet that copies and allocates the bytes into buf like: const Self = @This(); buf: []const u8 = undefined, header: *Header = undefined, pub fn initBuffer(allocator: Allocator, src: []const u8) !Self { const buf = try allocator.alloc(u8, src.len); errdefer allocator.free(buf); @memcpy(buf[0..], src); const packet: Self = .{ .buf = buf, .header = @ptrCast(@alignCast(buf[0…