Paul Mensonides <pmenso57 <at> comcast.net> writes:
I am not against having such a macro. I am against any form of treating an empty sequence of preprocessing tokens and whitespace separations (or one containing only whitespace separations) as a non-element in a data structure. "Empty" is a data element just as any other. E.g. () is not a nullary tuple, it is a unary tuple, and so on.
At some point you must make such a distinction simply because these concepts are treated differently between core language and preprocessor (for both C99 and C++) and even in the preprocessor itself. For the core language A() is a call with zero arguments. For the preprocessor A() is - a macro call with one argument, the empty one, if A has been defined to receive any argument - a macro call with zero arguments if the macro was defined to receive no argument I think any macros that are designated to be used by an "end user" must mediate between those different views and provide an end result that reads well for that end user, who I think expects syntax written as if it where core language. In P99 I use the IS_EMPTY macro for exactly that, try to accommodate that supposed expectation. Jens