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Comment by torben-friis | Hacker News Reader

Your elevator should not have automatic doors, doors are restrictive. They stop you from quickly jumping out of the elevator if you decide that you actually want to stay at the first floor.

Sure, we’ve seen some pretty gnarly accidents, and there is no reasonable situation where risking death is a sane choice.

But ask yourself: is it the elevator's job to prevent an accident? If you think so, I suggest you never leave your home again, as safety is your own concern.

Like and subscribe for other posts like “knife handles? What an idiot” and “never wear a helmet you coward”.

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> “never wear a helmet you coward”.

Unironically the biggest flame-wars I ever saw on forums back in the day was on whether or not mandatory bike helmets made cycling safer or more dangerous.

I can understand, I’ve had some awful bicycle accidents while not wearing a helmet and the helmet would have made no difference. My knees, hands and elbows have been through a lot but I have never hit my head. Even while skateboarding the one time I hit my head a helmet would not have helped. In hindsight I should have worn knee pads a lot more often but then I wouldn’t be able to tell if it’s gonna rain or not from the feeling in one of my knees :)

However if I had to ride on a public road with cars zooming pass me recklessly I would absolutely wear a helmet on a bicycle.

And there are countries where everyone rides a bike, and they are not usually the ones with mandatory helmets. When you hit someone with a bike you are less likely to kill them than when you hit them with a car, so more bike riding means less deaths, without even considering the effects of air pollution.

Helmets are fine for sport riding, but inconvenient if you want to ride 5 minutes to the shops on a whim. And that kind of riding is usually less intense and safer, I presume, anyway. Football has helmets, walking doesn't.

Those countries also have a higher number of brain injury cases vs countries where people wear helmets.

If you are hit by a car a helmet will do approximately nothing. However there are a lot of accidents that happen where you are not hit by a car where a helmet will help. (and even more when knee and elbow pads are what you need)

What if you're hit by a bike instead of a car because someone took the bike instead of the car?

A helmet can make a big difference in saving your brain if you are hit by a bike. Or if you hit a slippery spot and fall off your bike. Or - hundreds of other things that happen.

cars are too big and heavy for a helmet to make a difference - but they are not all that can go wrong. Even in car heavy US there is more than a car that can harm you.

Got it — helmets should be mandatory for pedestrians, in case they are hit by bikes.

Well unironically you would be safer if you did that! Although it's a trade off between looking ridiculous and being safe. I personally don't think bike helmets should be mandatory because it puts people off riding a bike (including me), but do acknowledge that they do make an individual safer.

Can't resist taking this bait, but I feel like the consensus is pretty much that as an individual, choosing to wear a helmet will make you safer, and as a society, mandating bike helmets (and other measures that will cause people to use transportation methods that are more dangerous to others) will make everyone less safe.

Of course, it's hard to prove. But I think you'll generally find that, if you compare the number of injuries/deaths while cycling in countries with mandatory helmets per km will be higher than it is in the Netherlands, where they are not mandatory.

Comparing the Netherlands with some of the best, if not the best bike infrastructure to other countries without said infrastructure seems very reductionist. To get anywhere near an interesting number you would have to compare the number of injuries to the total number of accidents including cyclists in countries with comparable bike infrastructure and differing helmet policies.

Yeah that's why it's hard to prove. However, it does show that infrastructure experts who actually care about safety (and have achieved the safety numbers to support it) reach for a lot of other measures before they do helmet mandates.

C programmers non-ironically believe this

And of course they only believe this because they don't lose a finger when they write outside of bounds or they don't fall down the shaft once a pointer was accidentally null

C programmers want program like they drive race cars or fighter jets, anything for greater speed

Did you even read the second half of the post? The author's answer to your concerns is testing. He suggests relying on tests rather than on strict type system that forces you to design everything upfront.

Personally, I can see arguments for both approaches - stricter types or more tests.

Yes I did, which doesn’t mean I buy the point at all. Testing clearly falls into “manually noticing the mistake”.

Tests check the operation for a single value of the, potentially infinite, input space.

Types check the operation for many, and can be made for all possible input values.

The difference is:

None of these boxes contain bicycles because:

* With tests: we checked 3 of them and found no bicycles

* With types: all the boxes are too small to contain bicycles.

I've written python and C++. For small simply problems python is nice, and writing tests for everything is easy enough. However as the program gets larger python becomes painful to work with. Writing code is the easy part, the hard part is when you want to refactor existing code to add a new feature - if you don't have the right tests (integration tests, not unit tests - though these terms are poorly defined) you will miss some code path that then won't work when it finally is run - unless you have a good type system which catches most of the errors that can happen when refactoring.

C++ is a notoriously difficult language to write in. However when the problem demands tens of millions of lines of code I'll take it over python because of the type system. There are other languages with good type systems that are reportedly better.

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