Hi all,

I am trying to write a small game with a tiled gameplay area. I have a vector of Tile objects - vector<Tile> area_tiles; - and I'm trying to add Tile objects to this vector like so:

Tile t();			// initialize new tile object
    area_tiles.push_back(t);	// and add it to vector

This is the way I have added objects to vectors in previous projects and it has always seemed to work (perhaps due to blind luck?), until now. When I try to compile, I get this error:

error: no matching function for call to `std::vector<Tile, std::allocator<Tile> >::push_back(Tile (&)())'

I am a rank beginner with C++ and have absolutely no idea what is wrong, and I'm not experienced enough to understand what the error message is trying to tell me. I am sure the root of the problem is painfully obvious to anyone who has a clue, if someone could enlighten me?

could you post where you declared the vector template (im assuming its a template) theres not enough information for me to help right now

could you post where you declared the vector template (im assuming its a template)

I'm afraid I'm not sure what you're asking for (this is probably indicative of my overall level of understanding).

He means when you declared area_tiles I think it might be the parens you have after t. You don't need them when declaring an object by the default constructor. Just do Tile t;

He means when you declared area_tiles

I have a separate class for the game area, and the vector of tiles is declared therein:

class Area
{
    public:

    Area( int y, int x );

    // stuff

    vector<Tile> area_tiles;
};

I think it might be the parens you have after t. You don't need them when declaring an object by the default constructor.

Cool, I didn't know that :)

Just do Tile t;

This gets me the following:

error: aggregate `Tile t' has incomplete type and cannot be defined

I guess this points to me having messed up somewhere else?

Post your whole code or attach it as files.

Post your whole code or attach it as files.

For clarity's sake, here is everything relevant.

#include <iostream>
#include <time.h>
#include <vector>

using namespace std;

class Tile
{
    public:

    Tile();

    int tile_type;
};

Tile::Tile()
{
    // select one of three types of tile
    tile_type = rand()% 3;
}

class Area
{
    public:

    Area( int y, int x );

    vector<Tile> area_tiles;
};

Area::Area( int y, int x )
{
    for ( int i = 0; i != y*x; ++i )
    {
        Tile t();
        area_tiles.push_back(t);
    }
}

int main()
{
    srand(time(NULL));

    Area game_area ( 20, 20 );

    return 0;
}

When I cleared the parentheses mentioned in the other post (line 35 in this code) I don't get any errors or warnings.

Try replacing Tile with Tile1 and also remove the '()' on line 35.

replacing Tile with Tile1

I'm not sure what the OP would gain from that.

I ran it and I got a vector of size 400 at the end of the Area constructor.

I wanted to check whether there is a naming conflict since the code has

using namespace std;

It could be something specific to the version that is being used.

Gotcha. Hadn't considered that.

Area::Area( int y, int x )
{
    for ( int i = 0; i != y*x; ++i )
    {
        // the compiler sees the below line as a function declaration,
        // 't' is a function that takes no arguments and returns a Tile.
        Tile t();

        area_tiles.push_back(t);
    }
}

So, the fix is to remove the parenthesis i.e.

Tile t;

Yes, it's been suggested. The OP hasn't reported back yet.

Yes, it's been suggested.

I know, it's just that the exact/real reason why that line is wrong hasn't been pointed out. Hence my two cents.

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