Is a variable named i unacceptable? [closed]

Answer 1

my feeling is that the concept of using a single letter is fine for "simple" loops, however, i learned to use double-letters a long time ago and it has worked out great.

i asked a similar question last week and the following is part of my own answer:

// recommended style              ●    // "typical" single-letter style
                                  ●
for (ii=0; ii<10; ++ii) {         ●    for (i=0; i<10; ++i) {
    for (jj=0; jj<10; ++jj) {     ●        for (j=0; j<10; ++j) {
        mm[ii][jj] = ii * jj;     ●             m[i][j] = i * j;
    }                             ●        }
}                                 ●    }

in case the benefit isn't immediately obvious: searching through code for any single letter will find many things that aren't what you're looking for. the letter i occurs quite often in code where it isn't the variable you're looking for.

i've been doing it this way for at least 10 years.

note that plenty of people commented that either/both of the above are "ugly"...

Answer 2

I am going to go against the grain and say no.

For the crowd that says "i is understood as an iterator", that may be true, but to me that is the equivalent of comments like 'Assign the value 5 to variable Y. Variable names like comment should explain the why/what not the how.

To use an example from a previous answer:

for(int i = 0; i < 10; i++)
{
    // i is well known here to be the index
    objectCollection[i].SomeProperty = someValue;
}

Is it that much harder to just use a meaningful name like so?

for(int objectCollectionIndex = 0; objectCollectionIndex  < 10; objectCollectionIndex ++)
{
    objectCollection[objectCollectionIndex].SomeProperty = someValue;
}

Granted the (borrowed) variable name objectCollection is pretty badly named too.

Answer 3

Here's another example of something that's perfectly okay:

foreach (Product p in ProductList)
{
    // Do something with p
}

Answer 4

If the "something more semantic" is "iterator" then there is no reason not to use i; it is a well understood idiom.

Answer 5

It depends. If you're iterating over some particular set of data then I think it makes more sense to use a descriptive name. (eg. filecounter as Dan suggested).

However, if you're performing an arbitrary loop then i is acceptable. As one work mate described it to me - i is a convention that means "this variable is only ever modified by the for loop construct. If that's not true, don't use i"

Answer 6

i is acceptable, for certain. However, I learned a tremendous amount one semester from a C++ teacher I had who refused code that did not have a descriptive name for every single variable. The simple act of naming everything descriptively forced me to think harder about my code, and I wrote better programs after that course, not from learning C++, but from learning to name everything. Code Complete has some good words on this same topic.