Re: Compilation failure: Iterator assignment in const member function
On May 15, 10:57 pm, acehr...@gmail.com wrote:
On May 14, 5:02 pm, sat_a...@yahoo.co.uk wrote:
This code fails to compile at (2) when I try to assign iterator. It
compiles if I remove 'const' qualification from the function at (1).
Is there a way I can have my 'const' and compile too?
#include <map>
using namespace std;
class Map
{
public:
void Func(int key) const // (1)
{
const map<int,void*>::iterator it = m_map.find(key); // (2):
fails to compile if 'const' is present
Either as already has been said use const_cast; or if makes sense for
your class, make m_map mutable:
}
map<int,void*> m_map;
mutable map<int, void*> m_map;
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extraneous material. - mod }
Setting map to mutable might defeat the purpose of the function being
a const function. The mutable keyword is used in those rare cases
where you want to be able to modify a member variable of a const
object, for some express purpose(for example, lazy evaluation).
I think just using the const_iterator is a better alternative to the
problem above.
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