[mnw21cam]

Indeed. The rule for prose is that a text block width should be somewhere between 2.5 and 3.5 full alphabets. This takes into account the variable spacing of different characters. This is to strike a balance between having inconsistent space or too much hyphenation (if the line is too short) and the eye's ability to find the next line when scanning leftwards from the end of the previous line (which is difficult if the line is too long).

Code is different in several ways. Firstly, code is generally shown in monospace typeface. Secondly, breaking lines too early can be even worse for code than for prose. Thirdly, even with a long line limit, code will generally have lots of short lines anyway, and this helps the eye find the next line when reading. The long lines (as long as they aren't all long) stick out from the rest of the code text, making it easier to read.