What is the scope of #define statement?
Say we have an inlude file as follows
---MyInclude1.h---
#ifndef MYINCLUDE1_H
#define MYINCLUDE1_H
#define EXAMPLE1 1000
#define EXAMPLE2 2000
#define EXAMPLE3 "Hello World"
#endif
---End of MyInclude1.h---
---MyInclude2.h---
#ifndef MYINCLUDE2_H
#define MYINCLUDE2_H
#define EXAMPLE1 "ABC"
#define EXAMPLE2 "DEF"
#define EXAMPLE3 3000
#endif
---End of MyInclude2.h---
If we include the MyInclude1.h and MyInclude2.h into my main program what
would be the value of EXAMPLE1,2,3 ?
2  5537 
Kay wrote: What is the scope of #define statement?
Don't you mean, what's the lifetime of the macro it defines? If so,
it's from the point of definition until the #undef for the same macro
or until the end of the translation unit preprocessing.
Say we have an inlude file as follows
---MyInclude1.h---
#ifndef MYINCLUDE1_H
#define MYINCLUDE1_H
#define EXAMPLE1 1000
#define EXAMPLE2 2000
#define EXAMPLE3 "Hello World"
#endif
---End of MyInclude1.h---
---MyInclude2.h---
#ifndef MYINCLUDE2_H
#define MYINCLUDE2_H
#define EXAMPLE1 "ABC"
#define EXAMPLE2 "DEF"
#define EXAMPLE3 3000
#endif
---End of MyInclude2.h---
If we include the MyInclude1.h and MyInclude2.h into my main program what
would be the value of EXAMPLE1,2,3 ?
What would be the value where? How do you include?
V
On Fri, 16 Jul 2004 12:29:33 -0700, Kay wrote: What is the scope of #define statement?
It is a simple text replacement. There is no scope at all.
Say we have an inlude file as
follows
---MyInclude1.h---
#ifndef MYINCLUDE1_H
#define MYINCLUDE1_H
#define EXAMPLE1 1000
#define EXAMPLE2 2000
#define EXAMPLE3 "Hello World"
#endif
---End of MyInclude1.h---
---MyInclude2.h---
#ifndef MYINCLUDE2_H
#define MYINCLUDE2_H
#define EXAMPLE1 "ABC"
#define EXAMPLE2 "DEF"
#define EXAMPLE3 3000
#endif
---End of MyInclude2.h---
If we include the MyInclude1.h and MyInclude2.h into my main program
what would be the value of EXAMPLE1,2,3 ?
You would be redefining the macros.
By the way, your compiler must have an option to show you what the
preprocessed output looks like. With g++, it is -E:
g++ -E mycode.cppb
Try the following definitions instead of macros:
int const example1 = 1000;
int const example2 = 2000;
char const * const example3 = "Hello World";
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