• Craig Bowlas <craigbowlas yahoo.co.uk> Jun 16 2006
• Walter Bright <newshound digitalmars.com> Jun 17 2006
• Craig Bowlas <craig bowlas.demon.co.uk> Jun 20 2006
• Walter Bright <newshound digitalmars.com> Jun 20 2006
• Craig Bowlas <craig bowlas.demon.co.uk> Jun 21 2006

Craig Bowlas <craigbowlas yahoo.co.uk> writes:

Hi,

The code ..

#include	"stdio.h"
using namespace std;
#include	<string>

struct	stuff
{
    string	a;
    string	b;
};

void	main	(void)
{
    stuff things[]=
    {
	{"bill","fred"},
	{"one","two2"},
	{"CD","DVD"}
    };
    
    for (int i=0; i<3;i++)
    {
	printf("item %d %s\n", i, things[i].b.c_str());
    }
}

produces the compiler errors 

        {"bill","fred"},
               ^
test.cpp(37) : Error: cannot find constructor for class matching
stuff::stuff(char const *)
        {"one","two2"},
              ^
test.cpp(38) : Error: cannot find constructor for class matching
stuff::stuff(char const *)
        {"CD","DVD"}
             ^
test.cpp(39) : Error: cannot find constructor for class matching
stuff::stuff(char const *)


If the types in the struct are built-ins (tested with int and char *)
and the initialisation array adjusted in the first case, the code
compiles and works as I would expect.

Is this a bug or am I being stupid?

Regards

Craig

Walter Bright <newshound digitalmars.com> writes:

Craig Bowlas wrote:
 #include	"stdio.h"
 using namespace std;
 #include	<string>
 
 struct	stuff
 {
     string	a;
     string	b;
 };


Any struct that has a member that has a constructor, must itself have a 
constructor. std::string has a constructor. Therefore, stuff must have a 
constructor.

Craig Bowlas <craig bowlas.demon.co.uk> writes:

On Sat, 17 Jun 2006 21:29:57 -0700, Walter Bright
<newshound digitalmars.com> wrote:

Craig Bowlas wrote:
 #include	"stdio.h"
 using namespace std;
 #include	<string>
 
 struct	stuff
 {
     string	a;
     string	b;
 };


Any struct that has a member that has a constructor, must itself have a 
constructor. std::string has a constructor. Therefore, stuff must have a 
constructor.


Thanks for the clarification, I found this issue while trying to
rebuild a code::blocks nightly with dmc and so I went to plan B and
attempted to use mingw/gcc for now.  

I have revisited the above and have added a constructor for the stuff
struct, but I still get the same errors, the code now reads ...


struct	stuff
{
    string	a;
    string	b;
    
    stuff(string c, string d);
    };

stuff::stuff(string c, string d)
{
    a=c; 
    b=d;
};

void	main	(void)
{
    stuff things[]=
    {
	{"john", "bill"},
	{"2", "one"},
	{"3", "CD"}
    };
    
    for (int i=0; i<3;i++)
    {
	printf("item %d %s\n", i, things[i].b);
    }
}
_____
Craig Bowlas                            craig bowlas.demon.co.uk

Walter Bright <newshound digitalmars.com> writes:

Craig Bowlas wrote:
 On Sat, 17 Jun 2006 21:29:57 -0700, Walter Bright
 <newshound digitalmars.com> wrote:
 
 Craig Bowlas wrote:
 #include	"stdio.h"
 using namespace std;
 #include	<string>

 struct	stuff
 {
     string	a;
     string	b;
 };


 constructor. std::string has a constructor. Therefore, stuff must have a 
 constructor.


 Thanks for the clarification, I found this issue while trying to
 rebuild a code::blocks nightly with dmc and so I went to plan B and
 attempted to use mingw/gcc for now.  
 
 I have revisited the above and have added a constructor for the stuff
 struct, but I still get the same errors, the code now reads ...
 
 
 struct	stuff
 {
     string	a;
     string	b;
     
     stuff(string c, string d);
     };
 
 stuff::stuff(string c, string d)
 {
     a=c; 
     b=d;
 };
 
 void	main	(void)
 {
     stuff things[]=
     {
 	{"john", "bill"},


try:
	stuff("john", "bill"),

 	{"2", "one"},
 	{"3", "CD"}
     };
     
     for (int i=0; i<3;i++)
     {
 	printf("item %d %s\n", i, things[i].b);
     }
 }
 _____
 Craig Bowlas                            craig bowlas.demon.co.uk

Craig Bowlas <craig bowlas.demon.co.uk> writes:

On Tue, 20 Jun 2006 15:48:43 -0700, Walter Bright
<newshound digitalmars.com> wrote:

Craig Bowlas wrote:
 On Sat, 17 Jun 2006 21:29:57 -0700, Walter Bright
 <newshound digitalmars.com> wrote:
 
 Craig Bowlas wrote:
 #include	"stdio.h"
 using namespace std;
 #include	<string>

 struct	stuff
 {
     string	a;
     string	b;
 };


 constructor. std::string has a constructor. Therefore, stuff must have a 
 constructor.


 Thanks for the clarification, I found this issue while trying to
 rebuild a code::blocks nightly with dmc and so I went to plan B and
 attempted to use mingw/gcc for now.  
 
 I have revisited the above and have added a constructor for the stuff
 struct, but I still get the same errors, the code now reads ...
 
 
 struct	stuff
 {
     string	a;
     string	b;
     
     stuff(string c, string d);
     };
 
 stuff::stuff(string c, string d)
 {
     a=c; 
     b=d;
 };
 
 void	main	(void)
 {
     stuff things[]=
     {
 	{"john", "bill"},


try:
	stuff("john", "bill"),

 	{"2", "one"},
 	{"3", "CD"}
     };
     
     for (int i=0; i<3;i++)
     {
 	printf("item %d %s\n", i, things[i].b);
     }
 }
 _____
 Craig Bowlas                            craig bowlas.demon.co.uk




Thanks Walter,
that does indeed compile and run as expected, thanks again

Regards

Craig
_____
Craig Bowlas                            craig bowlas.demon.co.uk