Is there a valid reason for enforcing a maximum width of 80 characters in a code file, this day and age? [closed]

Answer 1

I have two 20" 1600x1200 monitors and I stick to 80 columns because it lets me display multiple text editor windows side-by-side. Using the '6x13' font (the trad. xterm font) 80 columns take up 480 pixels plus the scrollbar and window borders. This allows one to have three windows of this type on a 1600x1200 monitor. On windows the Lucida Console font won't quite do this (the minimun usable size is 7 pixels wide) but a 1280x1024 monitor will display two columns and a 1920x1200 monitor such as an HP LP2465 will display 3. It will also leave a bit of room at the side for the various explorer, properties and other windows from Visual Studio.

Additionally very long lines of text are hard to read. For text the optimum is 66 characters. There is a point where excessively long identifiers start to be counterproductive because they make it hard to lay out code coherently. Good layout and indentation provides visual cues as to the code structure and some languages (Python comes to mind) use indentation explicitly for this.

However, The standard class libraries for Java and .Net tend to have a preponderance of very long identifiers so one cannot necessarily guarantee to be able to do this. In this case, laying out code with line-breaks still helps to make the structure explicit.

Note that you can get windows versions of '6x13' fonts Here.

Answer 2

I try to keep things down near 80 characters for a simple reason: too much more than that means my code is becoming too complicated. Overly verbose property/method names, class names, etc. cause as much harm as terse ones.

I'm primarily a Python coder, so this produces two sets of limitations:

1. Don't write long lines of code
2. Don't indent too much

When you start to reach two or three levels of indentation, your logic gets confusing. If you can't keep a single block on the same page, your code is getting too complicated and tricky to remember. If you can't keep a single line within 80 characters, your line is getting overly complicated.

It's easy in Python to write relatively concise code (see codegolf) at the expense of readability, but it's even easier to write verbose code at the expense of readability. Helper methods are not a bad thing, nor are helper classes. Excessive abstraction can be a problem, but that's another challenge of programming.

When in doubt in a language like C write helper functions and inline them if you don't want the overhead of calling out to another function and jumping back. In most cases, the compiler will handle things intelligently for you.

Answer 3

As the author of coding guidelines for my employer I have upped the line length from 80 to 132. Why this value? Well, like others pointed out, 80 is the length of many old hardware terminals. And 132 is as well! It's the line width when terminals are in wide mode. Any printer could also make hardcopies in wide mode with a condensed font.

The reason for not staying at 80 is that I rather

• prefer longer names with a meaning for identifiers
• not bother with typedefs for structs and enums in C (they are BAD, they HIDE useful information! Ask Peter van der Linden in "Deep C Secrets" if you don't believe it), so the code has more struct FOO func(struct BAR *aWhatever, ...) than code of typedef fanatics.

and under these rules just 80 chars/line cause ugly line wraps more often than my eyes deem acceptable (mostly in prototypes and function definitions).

Answer 4

There's already a lot of good answers to this, but it's worth mentioning that in your IDE you might have a list of files on the left, and a list of functions on the right (or any other configuration).

You're code is just one part of the environment.

Answer 5

I've widened my code out to 100 characters which fits comfortably in less than half my screen on my Macbook. 120 characters is probably the limit before lines start to get too long and complex. You don't want to get too wide else you encourage compound statements and deeply nested control structures.

The right margin is nature's way of telling you to perform an extra method refactoring.

Answer 6

I wonder if this might cause more problems in this day and age. Remember that in C (and possibly other languages) there are rules for how long a function name can be. Therefore, you often see very hard-to-understand names in C code. The good thing is that they don't use a lot of space. But every time I look at code in some language like C# or Java the method names are often very long, which makes it close to impossible to keep your code at a 80 characters length. I don't think 80 characters are valid today, unless you need to be able to print the code, etc.