[RC] Week #3: Journey through Ziglings

Context about what “Recursers” do day-to-day

See my Week #2 snippet for details.

Week 3 Progress

Completed 83.19% of Ziglings — tiny coding problems to learn the basics of Zig. How do I know the exact number? It’s because I added a progress indicator to my fork of Ziglings to keep myself motivated.

This worked well for me, so I proposed adding it to the Ziglings project, which was accepted and implemented right away! This was also a good learning exercise for me; see the section below on how I implemented the progress indicator vs. how the project owner implemented it.

Challenges

Social commitments: This part is still challenging; I missed “the impossible project” day (I wanted to try booting the OpenBSD kernel in the browser). Maybe next time. I changed my expectations from on-site “Recursers”; my experience is ultimately different. Not worse.
I adjusted my goal to build a healthy coding routine that works for me. I realized that coding daily is something I enjoy and was definitely missing out on in past years.

I am also starting to notice a gap in social life. I don’t speak Portuguese, so RC helps me have discussions in English once in a while (coffee chats are good for that!).

Details on Ziglings progress bar implementation

While it might be a trivial feature, it was a good first example for me to actually read some Zig code. It was even more interesting since it’s a change done via build.zig, which is how the Zig project builds itself. I really like that since I don’t have to learn another DSL (e.g., Bazel, CMake, etc.) to put a project together.

tl;dr:

• Math is different. I compute percentages using floats; Chris computes the size of the progress bar using unsigned integers.
• Memory management: I’m using a global mutable variable (boo!), while Chris allocates an array on the stack inside a function.

Specifically, I like this part:

fn printProgress(num: usize, max: usize) void {
	const bar_width: u32 = 60;

	const filled_len_u64 = (@as(u64, num) * bar_width) / max;
	const filled_len = @as(u32, @intCast(filled_len_u64));

There’s a lot going on with integer types here. usize is converted to u64, and then everything is converted to u32. I don’t know why.

	 var bar_buf: [bar_width]u8 = undefined;

	 for (0..bar_width) |n| {
		const ord = std.math.order(n, filled_len);
		bar_buf[n] = switch (ord) {
			.lt => '#',
			.eq => '>',
			.gt => '-',
		};
	}

This is the first time I’ve seen this kind of function, but I like this pattern.

	 std.debug.print("\rProgress: [{s}]  {d}/{d}\n\n", .{ &bar_buf, num, max });
}