Many years ago I had to try to debug a memory manager written by a really talented software engineer, with an interesting take on naming things…

• He referred to blocks of memory as “cookies”.

• He had a temporary variable named “handy” because it was handy to have around.

• He had a second temporary variable that referenced the first one that he called “son_of_handy”.

• If corruption was detected in a block of memory then it would set the flag “shit_cookie_corrupt”.

• If too many cookies were corrupt then the system would halt by calling the function “oh_shit_oh_shit_oh_shit”.

Does anyone have any good advice on variable naming? Here's some of my rules I try to live by:

• camelCase
• use prefixes
• prefixes should be one word followed by an underscore.
• 10 character limit or 3 word limit, not counting the prefix
• functions should be prefixed with the file in which they're defined, ie utils_FooBar
• file names should be one word
• Start Bools with is
• Don't use not in bool names.
  • This has farther-reaching implications that will keep you from making confusing code most of the time (I'm sure this will be controversial, but it works no matter what they say)
• start output with _
• Globals should be g_VARIABLENAME
• use the least amount of words possible
• but being too verbose can draw attention - use this to aide in readability
  • calc_ImportantValueThatWillDecideTheUsersView is better than calc_SumYears if the variable is more important than the others.
• Even the greatest variable names are not replacements for documentation
• Even the most readable code is not replacement for documentation.
  • Force yourself to love documentation.

Edit: I realize I was speaking about function-naming with the prefix stuff.

For variables, I still use prefixes, but for variable type. Even if you define the variables as types, it's still incredibly useful. For instance,

a string is s_MyName,

enumerable is e_MyType,

A number is int or double or whatever i_MyAge or d_MyWeight

This might be obvious for custom objects, but I'd still do it like this p_Person or per_Person.

Seriously it does make a huge difference