Re: map problem
csaba.trucza@gmail.com schrieb:
My first response was the same: char*'s will be compared as pointers.
Using Visual Studio 2008 I ran the following code, which as far as I
see reconstructs the OP's problem.
#include <map>
#include <vector>
#include <iostream>
using namespace std;
int main()
{
map<char*, vector<char*> > data;
data["foo"] = vector<char*>();
You don't need these. New values are default-initialized by the map.
data["foo"].push_back("foo.bar");
data["foo"].push_back("foo.baz");
data["bar"] = vector<char*>();
data["bar"].push_back("bar.bar");
data["bar"].push_back("bar.baz");
if (data.find("foo") == data.end())
cout << "not found" << endl;
else
cout << "found" << endl;
}
Strangely enough the output is "found". Anyone has an explanation?
"foo" is the same string as "foo". As optimization, Microsoft's compiler
will store the string only once in the executable and uses this string
for all occurances of "foo", so the pointers compare equal.
There's an option somewhere to turn this behaviour off.
--
Thomas
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