On Apr 18, 2011, at 7:41 AM, Stewart, Robert wrote:
Julian Gonggrijp wrote:
All this talking of underscores makes me wonder about private class members. Several authors advise to give them names with a prefix underscore (followed by a lowercase letter). It does seem to have clear advantages: it visually marks the members as implementation details, and it also makes it easier to distinguish class member data from arguments and locally declared variables in member functions.
However, your opinions probably differ wildly on the matter. Would you consider it good practice to give private class members a name that starts with _[a-z] (regex)?
Distinguishing private data members from local variables and formal parameters is useful. It creates a distinct "namespace" from local variable and formal parameter names. How to mark them is purely subjective. Some use the "m_" prefix, popularized by MFC and MSVC code generators, but I find that to be too much of a wart on the name. Some use "this->" as a prefix, so their data member names need no special marking.
I like to distinguish protected and private data members but with a trailing underscore. I use a trailing underscore because it is less important than the data member's name. (I also use a preceding underscore for formal parameters to give them another "namespace." In that case, the underscore can't be on the end, of course.)
I precede data member names with 'its_' (for nouns) or 'it_' (for boolean properties), e.g. its_window, it_is_selected. I chose third- person usage (as opposed to, say, "my") to match 'this'. I like self- documenting English notation. :-) Josh