I was meditating on Red Flags the other day.

M J D's Red flags and program repair material on perl.com has been very useful to me not just in coding, but in thinking about problems.

The most obvious red flags are
"don't do '($var1,$var2,$var3) = split', do '@vars = split"
and
"don't do "$user_name = $x; $user_rank = $y; $user_serial_number = $z', do '$user{'name'}', etc."

But there must be quite a few other ones that are key issues of good programming, plus there must be lots in specialised areas, like I see people getting very agitated about the use of placeholders in database contexts, which I don't care much about myself, but seems, just from skimming posts here, to be an important factor in good DB code.

Regexes also spring to mind as an example. Use of dot-star is always a bit worrisome, and do people know about the memory implications of using $& if you don't have to?

I was thinking of Red Flags as an area itself, or something to go in the Q & A area?

What do we think?
--

“Every bit of code is either naturally related to the problem at hand, or else it's an accidental side effect of the fact that you happened to solve the problem using a digital computer.”
M-J D

In reply to Should We Have A "Red Flags" Area? by Cody Pendant

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