do any of you others have little coding mantras that save your behind?

[Peter R Fletcher]

Don't compare datetimes for equality, either, particularly if they don't all come from the same 'source'.

[Member 9167057]

That, on the other hand, may work just fine. Depends on the language/runtime library and the source of the dates, but when I want to know if some date is today, equality works. Again, assuming the runtime library helps and you know what you're doing. There's a reason why TheDailyWTF has a couple stories on mishandling time stamps. I suppose, we could amend "Don't run home-built date/time handling" to the list of useful mantras. There's heap tons of ways to get them wrong and even if you test all you can, it may fail when a leap year occurs.

[AnotherKen]

Well, I more or less always knew that my greatest weakness was my tendency to want certain sections of my code to be bug free. That kind of code-blindness causes extra work when debugging. Through the years I have advanced to the point where I can realize now that I write loads of lines of bugs encapsulating some small bits of perfectly functional code. I'm actually a decent debugger now, I'm still working on the programming part.

[honey the codewitch]

AnotherKen wrote:

I'm actually a decent debugger now, I'm still working on the programming part.

Ha! relatable content :-D

When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.

[kalberts]

The REALLY big mistake is that the C# designers carried forward the old C way of reporting something non-numeric as if it were a numeric. IT IS NOT! The value of comparing A with B is either "A is less", "They are equal", or "B is less", NOT -1, 0 or 1. C# did abandon pointers as integers - "if (pointer)" is not valid; you must test "if (pointer != null)". They should have completed the job! Every now and then I get so frustrated over this that I write a thin skin for the comparisons, casting those inappropriate integers into an enum. But C# doesn't really treat enums as a proper type, more as synonyms for integers, so it really doesn't do it; it just reduces my frustration to a managable level.

[honey the codewitch]

The problem with that is they may not be 1, 0 or -1. Any positive value and 1 are going to have to be treated the same, and the same goes for the negative values - they're all -1, basically. But other than that, yeah. Although hate enums, because .NET made them slow. I still use them, but they make me frustrated. So usually in my classes where I don't want to burn extra clocks like my pull parsers I use an int to keep state, and cast it to an enum before the user of my code touches is.

When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.

[Peter R Fletcher]

Pure dates are generally not a problem, as long as you (or the coder from whose output you are getting the date) don't/didn't do something very stupid. Even here, however, timezone issues can cause problems. I once had an issue which resulted from the author of the firmware of a device I was getting data from recording what should have been a pure (midnight) datestamp as the corresponding local datetime. Since I am in the GMT-5 timezone, midnight on April 4 became 7 pm on April 3! Trying to compare datetimes for simultaneity, however, is almost always a severe PITA, when the source clocks are not both perfectly synchronized and using the same basic internal representation for clock time.

[Alister Morton]

If it ain't broke, fix it 'til it is. Oh, hang on - save your ass, you say?

[kalberts]

Sander Rossel wrote:

The popular "if you're doing single line if statements you're doing it wrong."

I had done quite a bit of Pascal programming when C came onto the scene. I have heard numerous arguments in favor of C, as opposed to Pascal. One of the major arguments against Pascal was "All that writing! All those keywords! It is almost like COBOL!" Essentially this referred to BEGIN-END. One-keystroke braces makes programming sooooo much faster... I have argued a lot about the impact on productivity from two or three extra keystrokes. Or fewer! Before C, no modern language required parentheses around a condition! No modern language required putting braces (or other delimiters) around single statements! The parser expects a block, and a single statement is a block! Then came this craze for LOC/day prouctivity measure. "My LOC/day is bigger than your LOC/day! So there!" The more lines you can spend on trivial things, the better programmer you are. Rather than

if ExpectedRainfall > 0 then BringTheUmbella;

you write

if (ExpectedRainfall > 0)
{
BringTheUmbrella();
}

- some programmers would even give the "if" its own line, putting the condition on a separate line. And lots of C programmers consistently add blank lines around every conditional statement and every loop. In the days of hardcopy listing, I frequently printed out source code double-spaced to give the impression of a lot of blank lines to make the code more readable. Screens were 24 lines tall at that time - that is not much. I wanted it to display 24 useful code lines, not twelve blank lines. I wanted that IF statement to use one of the 24 lines, not 4 or 5, plus a blank line. With C, we replaced a four-character keyword with two sets of (), one set of {} and 3-5 more line breaks, to reduce all that typing of writing "then"... But the modern mantra is "doing it like that single-line Pascal statement is wrong! The 4-5 line (+ blank line) solution with three sets of delimiters added is the right way to do it". I miss Pascal!

[TrinityRaven]

Don't return null. Throw an exception instead. Removes need to null check everything. Hopefully give a more meaningful error when a problem occurs.

[Rick York]

I used to let them test my stuff. They were really good at finding bugs and breaking stuff because they did unexpected things which was exactly what I wanted.

"They have a consciousness, they have a life, they have a soul! Damn you! Let the rabbits wear glasses! Save our brothers! Can I get an amen?"

[Rick York]

I have worked in the automation systems business for a long, long time and I found it is almost impossible to over-engineer things there. I wrote almost only because I haven't seen it happen yet.

"They have a consciousness, they have a life, they have a soul! Damn you! Let the rabbits wear glasses! Save our brothers! Can I get an amen?"

[Bruce Greene]

"Registered Nurse" to remember \r\n

[honey the codewitch]

Yikes! I'd hate to write code that way but to each their own. Null is often as not, a valid value, and not even a symptom of some sort of error. No way do I want to wrap my calls to a function that is expected to have null as one of its values with:

object result;
try {
result=Foo();
}
catch { result = null;}

more bugs, extra slow, and for no reason.

When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.

[Ira Greenstein]

My Mantra: "I'm too old for this ***t"

[kalberts]

Marc Clifton wrote:

Don't write an if unless you know what the else does and why.

I have seen programmers consistently adding "else /* do nothing */; after every "if" that doesn't have a natural "else". I think that clutters up both the logic and the code. Lots of operations are conditional; you perform them when conditions are met. Otherwise you don't, but you don't have to say that expicitly; that is obvious! It follows from the very idea of a conditional operation. Besides: I prefer to turn up the warning level to maximum while coding. When I take over code with zillions of empty "else"s, I get a zillion warnings about "possibly unintended empty staetement". What is the real difference between an "if" and, say, a "while"? You suggest that you always should indicate an alternative action when the condition is not met. So how to you specify the alternative action when the "while" condition is not met? If you do not, why not? Isn't that a very similar situation? Why is it less important to know what to do if a "while" condition is false than when an "if" contidion is false? Actually, I have used one language quite a bit where you could specify what to do when a "while" fails: you could conditionally break out of "for"-loops, and distinguish between breakout and completion of loop:

for listElement in listHead:nextpointer do
while listElement.key <> wantedKey;
exitfor
output ("sorry, the wanted key is not in the list");
exitwhile
output ("found! I can process this list element for you"):
endfor;

This is actually a very nice flow control construction, which is a mess to duplicate in C if you want the "exitfor" and "exitwhile" claused to exexute within the context of the loop (e.g. with access to loop local variables), which is one of the essential points. I honestly miss that flow construction. Why can't other languages offer it?

[kalberts]

If you remember to put the constant on the left side, you also would remember to double the equals sign. And why the h*** do we have to double the equals sign? This thread makes me miss Pascal so much! In Norwegian, "yoda" sounds like "joda...", ususally pronounced with a sigh, meaning "yes, but...". I hear what you say, but I am certainly not sure that you are right. So "yoda" may be an appropriate term :-) Pascal, and several other languages from that period, were designed by experts on formal languages, parsing etc. C is based on a collection of scraps left over from an early days space invation game implementation. OK, those students were certainly clever, but they were not experienced language designers.

[TrinityRaven]

Different use cases. I’m stuck debugging an app that is crashing because NULL is not a valid value. A part of what makes programming fun (?), is the various ways to solve a particular problem.

[honey the codewitch]

it's not just about remembering. It's about typos. A better argument is that compilers these days catch accidental assignment, but some of us have just had certain practices drummed into us for years and they stick. Double equals sign is necessary in the C family of languages because there are different ways to do equality and assignment. And you may find the C language family inelegant, but there's a reason they carried the day and pascal well... didn't.

When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.

[kalberts]

Students insist that when you measure up 3 kg of flour for your bread, that is count of the number of kilograms. Their body height is a count of centimeters. It goes the other way, too: They may use a float for the number of students in the class, arguing that when they increase the number by 1.0 for each newcomer, the float still represents the count of students. And, the more advanced ones argue, with a float, you can count any number of units. A plain int can't even count the number of living humans! Sure, most of these problem come with students who have been playing with computers in their bedroom since they were ten, all self-learned, having picked up one little bit here one there, with no trace of discipline whatsoever. But frequently, these become class heroes: Other students learn "smart tricks" from them, and "how real programmer do it, not the way that silly lecturer tells us to". So they can have a large influence on otherwise "innocent" students. This is mostly a problem with students. With professional programmers, the problem is with those who do not fully realize that e.g. a comparison does NOT return an integer (-1, 0, 1) but "less", "equal", "greater", and you should NOT compare it to numerical values. If you declare non-numeric, yet ordered, values as an enum, and create an array of, say, weather[january..december], you canNOT index this array with an integer, "because may is the fifth month, I can use 5 as an index... no, wait, I have to use 4, because it is zero based!" One specfic example: In my own C code, I use to define "ever" as ";;" so that an infinite loop, it is made explicit as "for (ever) {...}" (inspired by the CHILL language, where "for ever" is recognized by the compiler). I used this in one of the code modules I was responsible for at work. It was discovered by one of the young and extremely self-confident programmers, who was immensely provoked by it: He promptly replaced it by the "proper" way of writing an infinite loop: "while(1){..}". He searched through our entire codebase for other places where I had done similar sins, adding a very nasty remark in the SVN log for each and every occurance, requesting that everybody in the future refrain from such inappropriate funnyness - we should do our progamming in a serious manner. Oh, well - I din't care to argue. Why should I. Readable, easily comprehendable code is more essential when it will be read by people who are not into embedded systems code. Or rahter, to a developer of embedded C code,