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why can we not use function on left side of an expression in C ?

+7 votes
493 views 
#include<stdio.h>

int &fun()
{
   static int x;
   return x;
}   

int main()
{
   fun() = 10;
   printf(" %d ", fun());

   return 0;
}

It is fine with c++ compiler while giving error with c compiler.

posted Oct 29, 2013 by Vikas Upadhyay

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1 Answer

+4 votes

In C++ it is a reference so you can assign value to x;

For C you can achieve the same in the following way 

int * fun()
{
  static int x;
  return &x;
}

int main()
{
  *(fun()) = 10; 
  printf(" %d ", *(fun()));
}
answer Oct 29, 2013 by Salil Agrawal
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