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If the purpose of criticism is to improve the state of the art, then what is the point of unexplained criticism without alternatives? Other purposes of critici

If the purpose of criticism is to improve the state of the art, then what is the point of unexplained criticism without alternatives? Other purposes of criticism don't seem appropriate here. The abbreviations max and addr are found in colloquial English. Even phys is used in abbreviations like phys ed (physical education). Phys is the start of about 20 distinct words. Among them, physical has been the frontrunner in frequency since the late 1820s. [0] The only part of the abbreviation which would be confusing to a non-programmer, is the specific use of address in this context; but if you are working in a language which directly manipulates memory addresses, you should be able to expect that of the reader. maxPA is completely ambiguous (maximum pool allocations? maximum potential acceleration?), and it would need to be recalled, rather than recognized. On the other hand, MaximumPhysicalAddress is ridiculously huge, and would be impractical to use inline in an expression; at exactly twice the length of maxphysaddr, it conveys the exact same amount of information while being less practical to type, format, and read. Indeed, people might end up copying the variable to a local name just to fit it in their expressions. In C, it also conflicts with the common convention of making typedef'd struct names uppercase. [0]: https://books.google.com/ngrams/graph?content=physics%2Cphysical%2Cphysicality%2Cphysically%2Cphysician%2Cphysicist%2Cphysicked%2Cphysicking%2Cphysio%2Cphysiognomy%2Cphysiography%2Cphysiologic%2Cphysiological%2Cphysiologically%2Cphysiologist%2Cphysiology%2Cphysiotherapist%2Cphysiotherapy%2Cphysique&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cphysics%3B%2Cc0%3B.t1%3B%2Cphysical%3B%2Cc0%3B.t1%3B%2Cphysicality%3B%2Cc0%3B.t1%3B%2Cphysically%3B%2Cc0%3B.t1%3B%2Cphysician%3B%2Cc0%3B.t1%3B%2Cphysicist%3B%2Cc0%3B.t1%3B%2Cphysicked%3B%2Cc0%3B.t1%3B%2Cphysicking%3B%2Cc0%3B.t1%3B%2Cphysio%3B%2Cc0%3B.t1%3B%2Cphysiognomy%3B%2Cc0%3B.t1%3B%2Cphysiography%3B%2Cc0%3B.t1%3B%2Cphysiologic%3B%2Cc0 https://books.google.com/ngrams/graph?content=physics%2Cphys...

jmts 10y ago
To this I would like to draw attention to the mention of context in this example, which I think is important and often looked over when naming variables. The context given for maxphysaddr is that of a global variable. Pike also mentions loop indices, which have very local scope. A loop variable can be very short because you know everything about it simply by reading the few lines around it. A global must encode much more information in its name, because its context is spread globally. If the name is not good, the developer has to spend extra time looking for appropriate context, and aside from the added frustration, time is money. In some ways one could suggest that variable name length should be proportional to its scope. This isn't quite true, however, because we should then find that MaximumPhysicalAddress should provide greater value than maxphysaddr. Instead, we find that MaximumPhysicalAddress is a worse name due to its length. They are however both unambiguous and provide the same semantic information. This suggests that perhaps a rule of thumb should be that the name unambiguously encode the necessary semantic information proportional to its context, and no more. Naming is however hard, in general. It seems picking good examples is equally difficult.
- dwringer 10y ago
  That's exactly my point. I did not offer MaximumPhysicalAddress originally as an alternative, because as you said it is not really any less ambiguous in this case. However, a new programmer approaching the codebase still has to remember WHICH words are abbreviated and which variables rely on which abbreviations. Since MaxPhysAddr is already 11 characters long, and I can type MaximumPhysicalAddress in almost exactly the same amount of time (the overhead is essentially negligible) I see no benefit to using the abbreviated form. One must remember that maxphysaddr actually carries MORE information than MaximumPhysicalAddress, specifying that the words are all abbreviated. One can argue that the abbreviations used are conventional, but if the convention is not already known then the information required is even greater. That information is not relevant to the variable's function, and thus adds an unnecessary burden to the programmer. IMHO. But, again, it is not a good example, and I do not have a suggestion for an alternative.
deleted 10y ago
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dwringer 10y ago
"Other purposes of criticism don't seem appropriate here" - on that I will take your word; you've demonstrated quite an aptitude for inappropriate criticism. "Ridiculously huge" ? MaximumPhysicalAddress vs maxphysaddr, let's see, it is 22 vs 11 characters. Both are much longer than I'd want to type if speed or code byte size was a problem. For readability, the primary goal of all source code other than assembly (or code going out over-the-wire), it's not even close. If you really think maxphysaddr is as readable as MaximumPhysicalAddress, you hopefully recognize at least that not everyone would think that way. As for maxPA being ambiguous, well, yes. My point was that it's shorter. Perhaps one of the copied names programmers can use within their own expressions. Of course, they can use a find-replace and replace all those copies with MaximumPhysicalAddress in nearly an instant. Which is why it's probably the name I'd use unless I had to minimize byte size. If I had to minimize byte size, I would not waste time trying to compromise between length and readability. Otherwise I do not think there is ever a reason to compromise readability.

jmts 10y ago

To this I would like to draw attention to the mention of context in this example, which I think is important and often looked over when naming variables. The context given for maxphysaddr is that of a global variable. Pike also mentions loop indices, which have very local scope. A loop variable can be very short because you know everything about it simply by reading the few lines around it. A global must encode much more information in its name, because its context is spread globally. If the name is not good, the developer has to spend extra time looking for appropriate context, and aside from the added frustration, time is money. In some ways one could suggest that variable name length should be proportional to its scope. This isn't quite true, however, because we should then find that MaximumPhysicalAddress should provide greater value than maxphysaddr. Instead, we find that MaximumPhysicalAddress is a worse name due to its length. They are however both unambiguous and provide the same semantic information. This suggests that perhaps a rule of thumb should be that the name unambiguously encode the necessary semantic information proportional to its context, and no more. Naming is however hard, in general. It seems picking good examples is equally difficult.

dwringer 10y ago
That's exactly my point. I did not offer MaximumPhysicalAddress originally as an alternative, because as you said it is not really any less ambiguous in this case. However, a new programmer approaching the codebase still has to remember WHICH words are abbreviated and which variables rely on which abbreviations. Since MaxPhysAddr is already 11 characters long, and I can type MaximumPhysicalAddress in almost exactly the same amount of time (the overhead is essentially negligible) I see no benefit to using the abbreviated form. One must remember that maxphysaddr actually carries MORE information than MaximumPhysicalAddress, specifying that the words are all abbreviated. One can argue that the abbreviations used are conventional, but if the convention is not already known then the information required is even greater. That information is not relevant to the variable's function, and thus adds an unnecessary burden to the programmer. IMHO. But, again, it is not a good example, and I do not have a suggestion for an alternative.

deleted 10y ago

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dwringer 10y ago

"Other purposes of criticism don't seem appropriate here" - on that I will take your word; you've demonstrated quite an aptitude for inappropriate criticism. "Ridiculously huge" ? MaximumPhysicalAddress vs maxphysaddr, let's see, it is 22 vs 11 characters. Both are much longer than I'd want to type if speed or code byte size was a problem. For readability, the primary goal of all source code other than assembly (or code going out over-the-wire), it's not even close. If you really think maxphysaddr is as readable as MaximumPhysicalAddress, you hopefully recognize at least that not everyone would think that way. As for maxPA being ambiguous, well, yes. My point was that it's shorter. Perhaps one of the copied names programmers can use within their own expressions. Of course, they can use a find-replace and replace all those copies with MaximumPhysicalAddress in nearly an instant. Which is why it's probably the name I'd use unless I had to minimize byte size. If I had to minimize byte size, I would not waste time trying to compromise between length and readability. Otherwise I do not think there is ever a reason to compromise readability.