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Comment by singlow | Hacker News Reader

Or it represents one real thing that has multiple purposes outside the code and so the code can't fix that.

True.

But I've honestly never encountered this. Not in a valid domain concept. Where "valid" means it is truly embedded in the domain: and not some historical artifact that has been carried along for far too long¹

I'd love to see what valid real-world use-cases there are for an "FooOrBar" or "BarAndFoo" domain concept.

-- ¹ Which is a conundrum, I know. If some legacy system or even legacy software was badly designed (or not designed at all, but just evolved over time) carries along its "design flaws", after so many generations or iterations, it becomes the domain concept itself.

You've caveated the "valid" answers out of existence. But here are some examples of or-ed concepts:

* parent or legal guardian (shows up on legal forms all the time)

* state or province (an English language political construct)

* DNS name or IP address

You could argue that "parent of legal guardian" is a legacy concept since it really just means "legal guardian", but it's literally written on legal forms, so it's a domain concept, except if you believe it shouldn't count because it's an anachronism.

You could argue that we don't need "state or province" since we can just say "region", but "region" doesn't mean "state or province" colloquially, and we have to be careful not to refer to Ontario as a state, so the distinction is important. Ironically, that distinction does not exist in Chinese, but it does in English.

"DNS name or IP address" absolutely are two different concepts, it just happens that URL's were specced to accept both as the "host" segment. So whether or not it counts as an example depends on whether you believe that the act of coining the term is also the act of erasing its status as an "or" relation. Alternatively, if you're implementing a web browser, that distinction absolutely does exist because you need to know not to try to resolve an IP address as a DNS name.

I agree about the first two. The legal one being the most strong.

WRT "state or province": I've modelled quite some GIS data and tend to follow abstractions laid by OSM here. Where "state" is very different from "province" because in many locales that is the case;

But maybe your model is purely Chinese and the OSM model -albeit being global- has a poor local fit.

The latter: nah. It's the one I know about most, and I'd say, depending on your use-case, "address", "host", "location", URI, URL, etc are a better name for what you are modeling than "DnsOrIpAddress". If only for the fact that this can be read as "DNS Address Or IP address" as well as "DNS, or IP-Address". It is truly a bad name in many situations.

Fair enough, but you've surely encountered those first two before.

> But I've honestly never encountered this

Boy do I have the perfect example for you then: https://developer.apple.com/documentation/contacts/cnlabelco...

and, as many people pointed out, the actual domain concept is in Mandarin, and a single word.

So a perfect example of the word "Or" that does not denote a logical disjunction but a translation-artifact. I thought it was obvious that it is not literally implied the letters O and R are never allowed after each-other in code. I mean: obviously having a class named OrGate in an electronics simulation is fine. As is OrParty in a system modeling Israelian politics.

This is about the word Or denoting that your class, value, type, variable, model etc, is One Or The Other.

Then I'm not really sure what your point is. People were talking about the specific domain mentioned, then you said "or" is code smell regardless of domain, then people pointed out why it's _not_ code smell in this domain, then you come back and say "of course it's not code smell in this domain, I was talking about something else".

My point is that if you have a class, or method, or variable that represents "one thing, or another thing" this is a poor abstraction. And that you can "reek" this smell quite clearly if your names contain "one Or the Other" or "One And The Other" the words "Or" or "And".

The example you gave is an artifact of a translation. It is not an indication that this class holds either a "YoungerCousinMothersSiblingsDaughter" class/type/value Or a "FathersSistersDaughter". First, because AFAICS these separate things don't exist. And second because of the first part of that name: `LabelContactRelation`, it being a label; not a return value.

You did pay attention to the part where I explained that this, naturally, is not literally so, did you?

Right, I think you missed my point. If the example being discussed by everyone in this thread does not apply to your point, why did you bring it up in the first place and cause this confusion? And why did you say "Regardless of domain" if that's obviously not true?

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