Re: Problems declaring a map

From:
 James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Thu, 25 Oct 2007 02:21:54 -0700
Message-ID:
<1193304114.389007.223770@o38g2000hse.googlegroups.com>
On Oct 24, 8:46 pm, Erik Wikstr=F6m <Erik-wikst...@telia.com> wrote:

On 2007-10-24 19:39, LR wrote:

anon wrote:

Enric wrote:

I've the following code:

#include <map>
#include <string>

using std::string;
using std::map;

int sc_main(int ac, char *av[])
{
    map<char,string> start;
    map<char,string>::iterator si;
}

When I try to compile it :

main.cpp(55) : error C2653: 'map<char,class
std::basic_string<char,struct std::char_traits<char>,class
std::allocator<char> >,struct std::less<char>,class s

What I'm doing wrong?


You do not know the prototype for the main function.


Probably. But how do you know that. Maybe the name of that
function is sc_main. Would that be illegal?


Having a function called sc_main is not illegal, but the code the OP
posted is illformed since it does not have a proper main function (a
function called main returning an int).


C++ supports separate compilation, and there's no requirement
that any one specific translation unit contain a main.

I compiled his code with three different compilers (g++, Sun CC
and VC++) and the only errors I got were that the function
didn't return a value. (A warning with g++; an error with both
Sun CC and VC++---although it shouldn't be an error according to
the standard.)

His code is legal, as long as the function is never called (in
which case, it has undefined behavior because it falls of the
end without returning a value). Either he's compiling it with
the wrong options or something, so the compiler isn't treating
it as C++, or he has a problem with his installation (so the
compiler reads a corrupt version of <map> or <string>).

Can not see what? That the OP is using Windows or that his/her
compiler is set up wrong? The latter is obvious from the fact
that it does not compile perfectly valid code.


I've never yet used a compiler which compiles all perfectly
valid code---even Comeau has some bugs hidden in it somewhere.
Two of the three compilers I normally have access to fail to
compile the code because of the missing return, for example.

But in this case, yes. His compiler is either installed
incorrectly or he's using it incorrectly. If I add the return,
I have no problems with any of my compilers.

--
James Kanze (GABI Software) email:james.kanze@gmail.com
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