coding style - What kind of prefix do you use for member variables?

Question

No doubt, it's essential for understanding code to give member variables a prefix so that they can easily be distinguished from "normal" variables.

But what kind of prefix do you use?

I have been working on projects where we used m_ as prefix, on other projects we used an underscore only (which I personally don't like, because an underscore only is not demonstrative enough).

On another project we used a long prefix form, that also included the variable type. mul_ for example is the prefix of a member variable of type unsigned long.

Now let me know what kind of prefix you use (and please give a reason for it).

EDIT: Most of you seem to code without special prefixes for member variables! Does this depend on the language? From my experience, C++ code tends to use an underscore or m_ as a prefix for member variables. What about other languages?

Answer 1

No doubt, it's essential for understanding code to give member variables a prefix so that they can easily be distinguished from "normal" variables.

I dispute this claim. It's not the least bit necessary if you have half-decent syntax highlighting. A good IDE can let you write your code in readable English, and can show you the type and scope of a symbol other ways. Eclipse does a good job by highlighting declarations and uses of a symbol when the insertion point is on one of them.

Edit, thanks slim: A good syntax highlighter like Eclipse will also let you use bold or italic text, or change fonts altogether. For instance, I like italics for static things.

Another edit: Think of it this way; the type and scope of a variable are secondary information. It should be available and easy to find out, but not shouted at you. If you use prefixes like m_ or types like LPCSTR, that becomes noise, when you just want to read the primary information – the intent of the code.

Third edit: This applies regardless of language.