#undefine

[Helegurbann]

Has like this undef define in c++?Such as:

#define inti int 

#undefine inti2 inti
cout<<typeid(inti2).name();

[Disch]

I don't know what you're trying to accomplish with that second set of code.. but you can undefine macros with the #undef command:

#define foo int

foo bar;  // same as int bar;

#undef foo  // foo no longer is defined

foo baz;  // compiler error, foo is not defined. 

[Helegurbann]

I base to find invers define.I know #undef

[Disch]

I don't understand what you mean. Can you clarify?

[Zhuge]

Yeah. What do you mean by "inverse" define?

[Helegurbann]

Ok.

#define foo int
cout<<#undefined foo//#undefined or another transaction 

Output:

int

[Zhuge]

Like this?

#define foo int
#define quote(x) #x
cout << quote(foo);

[Helegurbann]

No.What is the aggregation transaction's reverse?
Answer:Abstraction transaction.
I am finding define transaction reverse.I want to reverse define transaction.

[Disch]

It's very difficult to understand what you mean.

If you're not asking about #undef, then I don't know what you need.

Can you can give more examples of what you need?

[hanst99]

I can't help but to think you are confused.

[Helegurbann]

Zhuge's exam output:foo.I want to find startest variable (int).ok?

#define foo int
#(my transaction) abc foo
cout<<abc;
Output:
int

[Zhuge]

As for getting a string literal...for the preprocessor to expand the macro, it needs to not be inside of another macro (like quote()). But without the quote macro, you won't get a string literal and won't be able to cout it. You could do something semi-hackish like so, though:

#define foo int
#define abc foo
abc x; // x will be an int
std::cout<<typeid(x).name()<<std::endl;

This uses typeid(), though, which is non-standard (I think).

[Helegurbann]

Yes.U apprehended me.

[Helegurbann]

bully for you :)

[Helegurbann]

U brainy person u:)