{"id":3678,"date":"2014-08-08T20:00:45","date_gmt":"2014-08-09T00:00:45","guid":{"rendered":"http:\/\/www.paleotechnologist.net\/?p=3678"},"modified":"2014-08-08T15:14:48","modified_gmt":"2014-08-08T19:14:48","slug":"how-not-to-code","status":"publish","type":"post","link":"https:\/\/www.paleotechnologist.net\/?p=3678","title":{"rendered":"How Not To Code"},"content":{"rendered":"

Recently, my friend Dan shared a thought-provoking picture of a quote by Martin Golding:<\/p>\n

 <\/p>\n

\""Always<\/a>

Words to live by.<\/p><\/div>\n

When I first started writing programs back in the Dark Ages (1980s), I wasn’t even aware that coding styles existed. Not only did I probably break every applicable rule in the Embedded C Coding Standard<\/a> — my code was usually cryptic, terse, and would have been very very difficult to scale.<\/p>\n

Nowadays, looking through my code library, I can almost tell when I wrote a piece of code, based on how it looks. Here’s an example of some of my oldest BASIC code that I could find: (The file, helpfully, was called “T.BAS”)<\/p>\n

5 PRINT TIME$
\n10 FOR X = 1 TO 1000000
\n20 P = 1 \/ X
\n30 NEXT X
\n40 PRINT TIME$<\/p><\/blockquote>\n

This is Dark Ages code for sure. No comments or other documentation whatsoever, single-letter variable names (the only reason TIME$ is there is that it’s built-in), and LINE NUMBERS. Fortunately, this program is very simple, so it’s an easy enough task to figure out what it does. (It’s a very simple benchmark for a division loop.)<\/p>\n

Here’s how I might write it these days:<\/p>\n

‘Division loop benchmark test program (FreeBASIC)
\n‘Notes time to execute one million divisions of size double
\n‘M. Eric Carr \/ eric(at)(email address)<\/p>\n

‘Variable declarations
\n‘———————-
\ndim as double quotient
\ndim as ulongint curNum<\/p>\n

‘Note the start time
\nprint “Doing 1,000,000 divisions…”
\nprint “Started at: “;time$<\/p>\n

‘Run a loop of 1,000,000 divisions
\nfor curNum = 1 to 1000000
\nquotient = 1\/x
\nnext curNum<\/p>\n

‘Note the end time
\nprint “Ended at: “;time$<\/p>\n

end<\/p><\/blockquote>\n

This is a little better. It’s still flat code (no subroutines or other hierarchical structure), but it’s simple enough that such structure isn’t really needed. The documentation and intuitive variable names make it much easier to maintain, the output now tells the poor clueless user what is going on, and the global variables are at least declared.<\/p>\n

Here are some other helpful tips to make your code more maintainable:<\/p>\n