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Comment by mxschumacher | Hacker News Reader

> You want names to be short, so you easily write and read them. Especially if you use them a lot, it's useful to use abbreviations, like x, e, i, z.

when I look through older C codebases (Python, Linux), I often notice the extremely short and cryptic names. I wonder whether this practice is an artefact of a time before auto-completion & automatic refactoring?

These days, you can use meaningful names without much typing. From a reading perspective, I believe that longer names (within limits) are easy to parse. Humans see words, not characters.

E.g. When I first understood that argc means "argument counter" and that argv stands for "argument vector" it was a little revelation to me.

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This has probably been said a dozen times already, but short symbol names are indeed acceptable in various situations, including but not limited to:

- Where they are actually correct, such as dimensions (x, y, z) or vectors (j, k, l, u, v, w).

- Other mathematical symbols (N, M, e, t). Maths is also a special case in which I'm personally willing to do away with usual variable naming conventions, for example when translating formulas from a scientific paper into program code.

- Very short code, e.g. lambdas (lambda x: x2), list comprehensions ([p.title for p in posts]) or simple loops.

If you look at SQLite, you'll notice that most variable and struct field names are short and cryptic, and that library is still considered a high-quality piece of code.

Regardless, I don't understand all the downvotes you're getting.

> list comprehensions

Yes. Very much yes. My personal rule is to _always_ use single-letter names for Python comprehension indices, because line length is the biggest enemy of readability there.

IMO short names are perfectly acceptable and even preferable as a local variable names withing short functions, when context is obvious and everything fits onto one screen. I would prefer

    for (int i = 0, len = string.length(); i <= len; i++) {
        char c = string.charAt(i);
        if (c == '\t') {
            return true;
        }
    }
    return false;

rather than something like

    boolean tabFound = false;
    int stringLength = string.length();
    for (int characterIndex = 0; characterIndex <= stringLength; characterIndex++) {
        char character = string.charAt(characterIndex);
        if (character == '\t') {
            tabFound = true;
        }
    }
    return tabFound;

Naming a variable solely after its type is never particularly useful. A name like `currentChar` would probably enhance readability. Of course if your code is just 2 lines long, `c` works just fine (that's not usually the case though).

You should probably abstract away some of that logic though (and `string` isn't a great variable name either):

    boolean tabFound = includes(line, '\t');

How would you name an abstract string without any implied meaning?

If the functionality you're writing is truly that abstract, an abstract variable name is fine. Your example didn't include the method signature though, so I assumed it was a part of some larger (concrete) code block.

In my experience, one-character variables are serviceable, even preferable, when you're piping data, like Streams in java, or all the equivalent functions in rust. So long as the starting input's type is clear, the "capturing" variable can be just the first letter of the type.

> When I first understood that argc means "argument counter" and that argv stands for "argument vector" it was a little revelation to me.

I was today years old... :|

Some of the oldest C compilers had a hard limit of 8 characters for identifiers. Those limits were removed decades ago but old habits die hard.

I personally prefer short and cryptic names for things that are used very often, but don't shoot the messenger. My main point are the trade-offs.

Some of that is from mathematics, for example (random code from the Internet):

   reverse2 xs     = go [] xs
       where
       go ys []     = ys
       go ys (x:xs) = go (x:ys) xs

In general, more abstract you get, the less important it is to devise long names, because things are going to be abstract anyway. Often, all you can tell about the object is already encoded in the type system.

Even in current practice, people prefer "log.info(..)" to "centralizedLoggingSystem.informationalMessage(..)". They prefer "Exception e" to "Exception unexpectedlyFailedToWriteAccountingFileException". We also prefer to write "a * b" instead of "a.multiplyBy(b)".

Sometimes simply the global consistency trumps the local context.

> E.g. When I first understood that argc means "argument counter" and that argv stands for "argument vector" it was a little revelation to me.

This is something every hello world tutorial should point out, but obviously most of them leave a lot to be desired. Or "argument count," as I know it, not "counter".

To me, most abstraction used in computing is done to provide way for a reductionist view of something. Abstractions don't have to be reductions but in practice, that's what they're typically used for.

Because of this, whenever you're reducing something you inherently peel off information and it's lost to 'simplify' something. This is where all sorts of forms of documentation come in handy: they provide a venue to retain and share some of that lost information you think might be critical and explain those 'simplification' assumptions.

In the above, information for reductionist abstractions often get lost over time when people make assumptions and don't share them in some form. Once you understand the original meaning--information that was lost, often times if well designed, everything falls into place for understanding fairly quickly.

I recently saw a post somewhere explaining why "uppercase" and "lowercase" described characters due to historical context where on printing machines, what we know as uppercase letters were stored in the top of the case while what we know as lowercase letters were stored in the bottom of the case (hence the upper and lower cases). Most my life I just assumed "upper" meant "bigger" and lower meant "smaller." In this particular case, that lost nomenclature information didn't add much value (although interesting). In some cases, it does (like the argc and argv information pointed out). Choosing what information to reduce and carry forward is an art form. You also have to be careful when teaching about what assumptions you take for granted that most don't start with.

I'm a believer in understanding at least one level beyond what an abstraction system is doing for me. It's not the most efficienct thing, but it demystifies the abstraction and when you run into hurdles introduced because the structure of that abstraction, you know why and often can devise ways to fix it. It's not always possible and in some cases isn't worth it.

Most modern software development has so many high level abstractions that understanding even one level down is typically impossible for any sane person given typical resource constraints for a given API. Because of this, we run into all sorts of messes where were drowning in abstractions (that aren't very standardized or widely adopted, instead composed together in case by case basis) we don't understand (i.e. complexity). That's all well and all until those abstractions fail and you're the person responsible to repair/mend them back into usefulness for a particular case--then it's a nightmare.

Personally, I can stand abbreviations so long as they're pronounceable. I think phonetic syllable-granularity abbreviations are an optimal tradeoff. argumentVector is silly to be writing in full all the time but argv is infuriating.

When I parse code I'm mentally reading to myself, so argv is deplorable gibberish that has to be translated to "arg-vee". It's like traveling over rocky ground, one step is easy enough but over a distance it really slows you down. argvec saves almost as many letters, is way more readable, abbreviates both words down to the same scale, carries more semantic meaning through for a newbie, etc.

Some English words can't be phonetically abbreviated and I think those are better off written in full.

> and that argv stands for "argument vector"

Huh wow, I've never actually been taught what argv stands for and have gone my whole life (post learning C) assuming it means Argument Values.

x is a variable name I still use quite a lot. Because it is quite meaningful as 'a meaningless parameter that is just a variable'. Same with y and z, though less often.

I'd also say that short names are sooner a product of line-length limitations than refactoring. Having to spread out every single statement over many lines because your reference a 12 character function 3 times in the same line and you are limited to 80 characters sucks.

Point taken that it is ok to use i, x, y, z sometimes (eg. when iterating), but the notion 'a meaningless parameter that is just a variable' doesn't really exist... if it's meaningless, why are you saving it?

Only other use case I can think of is doing metaprogramming or some sort of templating where you have a variable, but might no even know what it represents, because it isn't your concern.

> if it's meaningless, why are you saving it?

Because you are writing abstract code.

Odds are that a lot of your code is better done abstract, and only fully specified in a short context.

What about implementing something like map for lists? You know literally nothing about the values and the function except for their types.

    map :: (a -> b) -> [a] -> [b]
    map f [] = []
    map f (a:as) = f a : map f as

Personally I don't see any reason to use longer names than f, a, and as because you can't add any additional information.

You might say "well I don't write code like that", and I don't have any answer for you. But I find I write a fair amount of generic code.

> you can't add any additional information

Well you could...

    map transforming_function (element:rest_of_list) = transforming_function element : map transforming_function rest_of_list

...but the cost in terms of loss of brevity would far outweigh a benefit that would only accrue to complete beginners, who would be better served by comments and test cases.

A variable can be a substitute for a longer expression for which a name/description is unnecessary because the expression itself is self-explanatory. The substitution with a (essentially meaningless) short name just makes repeated use of that expression more readable. Using a long, descriptive name would defeat the point.

Maybe it's also time to loosen the 80char limit a little bit, screen resolutions have advanced dramatically and large screens are commonplace.

I'm not a fan of sacrificing readability for some arbitrary screen-width limitation.

Going up to 100 or 120 is already sufficient

You'd need to make a case of which value, and why, and why it is better, so that the terminals can standardize on it.

I actually like the limitation, because it makes me use more enters, so that the information ends up not within one line but in multiple. Which mans more lines (and LOC) but better readability.

I guess a good comparison is Twitter's limitation on the characters. It has its pros and cons.

Contrariwise, I try to keep my code under 72 columns wide, and impose a hard limit at 80. Long lines are hard to read, no matter what screen they're on.

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