c - Is there a way to redefine a struct? -


i not trying have 2 different structs same name, rather defining same exact struct 2 different times (probably in different header files).

for example:

struct foo {     int bar; };  struct foo {     int bar; };

gives error.

the way surround struct preprocessor instructions

#ifndef struct_foo #define struct_foo  struct foo {     int bar; };  #endif /* struct_foo */  #ifndef struct_foo #define struct_foo  struct foo {     int bar; };  #endif /* struct_foo */

this has effect of defining struct foo once. in combination commonly accepted practice of putting such item in file called foo.h, so

#ifndef include_foo_h #define include_foo_h  struct foo {     int bar; };  #endif /* include_foo_h */

it protects against person doing

#include "foo.h" #include "foo.h"  (rest of code)

as far redefining struct, not permitted in c language; however, can things approximate non-full redefine. recommend avoiding them, tend make code more obscure , difficult maintain.


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