cout << "hello, world" << endl;
This made the C programmer in me squirm. Why would you make the meaning of operators change wildly based on the context? Also you might lose track of what code is actually being generated. It could have side effects that you don't know about, or be orders of magnitude slower! I still fill this way, and avoid operator overloading, other than operator=, for most things.
...but having said that, I find operator overloading to be incredibly valuable when it comes to maintaining and refactoring a large code base. A pattern that has become routine for us is a basic type is initially used for some state and needs to be extended.
For example: in track groups, we originally had 32 groups (1-32), and a track could have different types of membership in any number of groups. For 32 groups, we used unsigned ints as bitmasks. Some years later, to support 64 groups we changed it to WDL_UINT64 (aka uint64_t). Straightforward (but actually quite tedious and in hindsight we should've skipped the type change and gone right to the next step). To increase beyond 64 bits, there's no longer a basic type that can be used. So instead:
struct group_membership {
enum { SZ = 2 };
WDL_UINT64 m_data[SZ];
const group_membership operator & (const group_membership &o) const
{
group_membership r;
for (int i = 0; i < SZ; i ++) r.m_data[i] = m_data[i] & o.m_data[i];
return r;
}
// and a bunch of other operators, a couple of functions to clear/set common masks, etc
private:
// prevent direct cast to int/int64/etc. necessary because we allow casting to bool below which would otherwise be quietly promoted to int
operator int() const { return 0; }
public:
operator bool() const { for (int i = 0; i < SZ; i ++) if (m_data[i]) return true; return false; }
};
Then we replace things like:
WDL_UINT64 group;with
group_membership group;
and after that, (assuming you get all of the necessary operators mentioned in the comment above) most code just works without modification, e.g.:
if (group & group_mask) { /* ... */ }
To be fair, we could easy tweak all of the code that the operator overloading implements to use functions, and not do this, but for me knowing that I'm not screwing up the logic in some subtle way is a big win. And if you have multiple branches and you're worried about merge conflicts, this avoids a lot of them.
Also, it's fun to look at the output of gcc or clang on these things. They end up producing pretty much optimal code, even when returning and copying structs. Though you should be sure to keep the struct in question as plain-old-data (ideally no constructor, or a trivial constructor, and no destructor).
Thus concludes my "a thing I appreciate about C++" talk. Next week, templates.
Recordings:
super8_novideo - 1 -- [9:36]
super8_novideo - 2 -- [4:16]
super8_novideo - 3 -- [4:34]
super8_novideo - 4 -- [8:20]
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This was a picture I took soon after I got my 400mm lens in 2001, with my first DSLR, a Canon D30. I’m actually surprised how much better the 6Dmk1 looks (even not considering the much higher resolution), at the time I thought the D30 was amazing…
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Red-tailed Hawk, Hunting:
Eastern Phoebe:
Northern Mockingbird:
Merlin says this is an Eastern Phoebe, which I believe:
And a Hermit Thrush, so cute:
And this Cardinal by himself:
Then a Cardinal love triangle elsewhere:
We drove to LA.
(this dog barked at me until I acknowledged him at the red light)
The (almost)-annual pilgrimage to Tacos Delta. Saw Paranorm. ChatGPT told us (and Wikipedia eventually confirmed) that Tarzana was named after the creation of its resident Edgar Rice Burroughs. Steve walked 15 miles the day before the race (!).
drop bags
Gear for the race:
The race -- forecast was a low of 55 and a high of 72. Turns out the start was considerably colder, though, due to microclimates of the valley. But it was still quite pleasant having so recently been in the 20-degree highs of NY.
Psyched sideways
The first half of the race was more of a run than a race, as these things go.
The race begins on a road. Hey wait.
The water crossing at mile 2 was quite a bit higher and unavoidable this year. In 2020 I managed to keep my feet dry. The wool socks I was wearing quickly dried out and didn't give me any problems.
I changed my shirt and hat and dropped off my headlamp at the drop bag at mile 13, around that time I noticed some bits of chafing in spots, put some bodyglide on there and it stopped being a problem.
Peanut butter pretzels were good, stroopwaffels too. I think I might have accidentally dropped a wrapper though, ugh, sorry, hopefully someone picked it up. I put it in my pocket and closed the zipper but when I went to open the pocket at the aid station to dump the trash it was gone. Or maybe I misplaced it. Your brain sometimes loses track of all of these things.
why didn't someone tell me that water bottle looks ridiculous in the pocket?
group of mountain bikers having lunch, I assume. nice spot for it.
this time, on the descent to Bonsall, I could see the trail across the valley that we would later be on. makes me giddy!
settling in to the race and getting ready to fall apart at mile 22, Bonsall
At mile 22 I stopped, saw a guy (hi, Peter) whom I had previously mistaken for Steve, put some squirrel nut butter and a bandaid on a hotspot on my big toe (worked well, never used that stuff before). Filled up to the brim with water.
(crows getting a free ride on the ridge)
I paid more attention to birds this year, and not just the crows. I'd like to go back to these trails with a camera and big lens and time to spare.
The massive climb out of Bonsall was nice since I knew what to expect (in 2020 it was demoralizing, lol), but it was really hot. There was a stream crossing where dipping your hat in the water was an amazing feeling (though within minutes it was back to heat). If I had more time I would've sat in it.
The second half of the race was more difficult. I no longer had the energy to take pictures. The aid station around the halfway point had a lot of bacon. I really wanted some but I couldn't bring myself to eat any. This seems to happen to me at this point, nausea and stuff. I need to figure this out (brain thinks I have food poisoning or something?). Maybe I should've tried a gel. Doesn't require chewing and pure sugar, might have been worth the try. Hindsight.
At mile 37-ish, drop bag again, grabbed lights, long sleeved shirt, other hat. Didn't want to mess with my socks so kept my original pair.
I kept moving, snacking a little bit here and there, trying to down some tailwind along with the water, hanging on. By mile 43 (nearly 11 hours after the 5:30am start) I was 5 minutes ahead of my 2020 time, and only 10 minutes behind Steve, but I really couldn't eat anything. I overhead a couple of people drop to the 50 miler. My legs felt OK, and it turned out if I continued on with the 100k route, I could always drop at 50 miles (since it was a 6-mile each way out-and-back that turned around near the finish). So I continued on. Up a hill, then down a really massive hill. Going up the hill was fine. Going down the hill was difficult. I haven't done enough quad strength training. Tsk tsk. I ran a little bit of it but it was mostly walking. Ate maybe 3 almonds, drank a few swigs of tailwind. It was starting to get dark. At the bottom of the hill it was along a riverbed for a while. Lots of frog sounds. I saw Steve when I was about 15 minutes away from the 50 mile aid station (so his lead was up to about 30-45 minutes at that point, I guess?).
The aid station people gave me a quarter of a banana, which I ate. It was not easy. They were nice (they are all). Someone I talked to earlier in the race asked if I had a pacer for this part, then looked at me like I was crazy for not. I remembered this, and asked if there were any freelance pacers available. No such luck.
Did the riverbed commute back to the climb, now with my head(waist)lamp on. Coming down the hill was a race marshall, sweeping the course. Nobody else would be coming down the hill. I could see headlamps far ahead, and occasionally see them far behind me, but for a long time I saw nobody, and heard only the sounds of frogs and wind. The moon rose, it had a lot of clouds in front of it and looked very red on the horizon.
I running a huge calorie deficit and was having to regulate my climbing of the hill in order to prevent bonking. I'd go too hard and have to back off because I could feel it wouldn't be sustainable. This was the toughest part of the experience, I think, this climb. When I was eventually caught by another runner, it was nice.
Going over the hill and back down to the mile 43 aid station (again, though now at 55-ish), with 7 miles to go. This aid station is a bit remote and you can't drop out of the race there, and I guess it was getting late, so the aid station captain was really big on getting me moving. Tried to get me to eat, but when I did my best picky eater impression he said (very nicely -- everybody volunteering at the aid stations were amazing) something to the effect of "well water is what you need most right now, now get moving." So I did. I ended up not having any real calories to speak of for the last 20 miles of the race, heh. Though almost all of those 20 miles were walked, not run.
After that final aid station, the last 7 miles were challenging but also pretty straightforward, the finish was within reach, and I had plenty of time to not hit the cutoff at a walking pace. My underwear had bunched up and I had some pretty significant butt chafing but it was too late to do anything about it, just had to suffer with it. Should've checked in for it hours ago, doh. Once I got to the flat ground of the last mile, walking at about 13 minutes/mile to the finish felt pretty good (flat!). I was sort of hoping to be DFL, but not enough to slow down when I saw some headlamps behind me.
After more than 16 hours of running and hiking, Steve was waiting for me at the finish (having waiting 90 minutes! <3). There was food, but it would be hours until I could eat anything meaningful. We headed back to Tarzana, and watched some TV (was it Boys or 30 Rock? I can't remember) before crashing.
I got the shivers again. Seemed to be associated with movement, too. Didn't last too long, and not so bad. Way better than covid. Apparently it's about inflammation.
The next day Edward made us steak. Amazing.
There was ice cream, and a cold swim in a 55F pool. Total win.
Am I ready to do this race (including its 13,000ft of climbing and descent) again? No. But it won't be long.
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