Re: Vector iterator problem
On 8/4/2011 12:14 PM, Nephi Immortal wrote:
I guess that Microsoft?s vector code is not good because iterator is
less flexible. If you want to use operator<= or operator>, then
assert is triggered.
I suppose to use operator> if I don?t want to use reverse_iterator.
Why do vector documentation tell to use only operator!= or operator<?
I wish Microsoft should rewrite their vector code. All iterators
must always use signed integer instead of unsigned integer.
I don't understand what you're griping about. I just took your code,
and ran it through the Visual C++ 2010 compiler with NO ERRORS.
Could it be you're using an older version? Get the new one already.
#include<vector>
using namespace std;
int main()
{
vector< int> a;
a.push_back( 1 );
a.push_back( 2 );
a.push_back( 3 );
a.push_back( 4 );
vector< int>::iterator B = a.begin();
vector< int>::iterator E = a.end();
vector< int>::iterator I;
int _v;
// OK
for( I = B; I != E; ++I )
_v = *I;
// OK
for( I = B; I< E; ++I )
_v = *I;
// ERROR
for( I = B; I<= E; ++I )
_v = *I;
^^^^^^^^
This code has undefined behaviour when I==E.
/* operator<= should call operator< automatically */
// ERROR
for( I = E; I != B; --I )
_v = *I;
// ERROR
for( I = E; I> B; --I )
_v = *I;
return 0;
}
--
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