Re: map problem
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*>();
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?
The compiler will only emit a constant string once & use the same pointer
each time.
try...
#include <stdio.h>
int main()
{
char* a="foo";
char* b="foo";
printf("%08x, %08x\n",a,b);
}
with GCC 3.4.4 under cygwin on 32bit Wintel box I get 00402000, 00402000 as
the output. a & b are set to the _same_ pointer.
Chris
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