Making intellisense acknowledge variables declared inside macros

The time-saving technology of intellisense is a real bonus for all of us who use variables with a little more meaning to their names than m_nOad. Among other things, it allows for parameter info (far less F1 inquiries) and member info. However, if the variable you are trying to use Intellisense on is not explicitly defined, but rather defined in some kind of macro (as is the case in certain MFC and ATL macros), one cannot use that variable with intellisense.

The simplest way of avoiding that problem is using Intellisense's own disadvantages to our advantage. Take for example the following MFC custom interface implementation code:


HRESULT CSomeClass::XSomeInterface::SomeMethod(long SomeParam)
{
 METHOD_PROLOGUE(CSomeClass,SomeInterface);

 // If I were to write pThis-> now, I would
 //not get the expected drop down list of members.
}
To solve this, we will actually define the variable, only make the compiler ignore it:

HRESULT CSomeClass::XSomeInterface::SomeMethod(long SomeParam)
{
 METHOD_PROLOGUE(CSomeClass,SomeInterface);
#ifdef SOMETHING_WHICH_IS_NOT_DEFINED
CSomeClass* pThis;
#endif
 // If I were to write pThis-> now, the list would
 // pop-up and give me the list of members. Problem solved.
}
Now, this will make your code a little less readable, and is a drag to write each time. Instead, we can do the same thing to define something that intellisense will recognize as a "global variable":

In your implementation code, at it's beginning, repeat that same #ifdef sequence.


#include "this.h"
#include "and_that.h"
#ifdef SOMETHING_WHICH_IS_NOT_DEFINED
CSomeClass* pThis;
#endif
Now, in your method implementation:

HRESULT CSomeClass::XSomeInterface::SomeMethod(long SomeParam)
{
 METHOD_PROLOGUE(CSomeClass,SomeInterface);

 // If I were to write pThis-> now, I would
 // get the expected drop down list of members without
 // "declaring" that variable again and again.
}
Note: The example given here was about MFC's implementation of custom interfaces, however, it's true for every place you have macros defining variables. The global method, when not applied correctly, will yield unexpected intellisense behavior.

Date Last Updated: February 4, 1999