I am attempting to write a basic first program in allegro

Question

SO, I'm using the latest version and the latest version of Allegro, but on lines 6 and 12 I seem to have encountered some errors that are not yet clear to me. I am very new to C++ as well as Allegro, so any help would be very much appreciated.

For line 6 I have the error message: "expected identifier or '(' before string constant For line 12, I have the error message: "'display' undeclared (first use in this function)

#include<allegro5/allegro.h>
#include<allegro5/allegro_native_dialog.h>

    int main()
    {
        ALLEGRO_DISPLAY "display";

        if(!al_init())
        {
            al_show_native_message_box(NULL, NULL, NULL, "Could not initialize Allegro 5", NULL, NULL);
        }
            display = al_create_display(800, 600);

            if(!display)
        {
            al_show_native_message_box(NULL, NULL, NULL, "Could not create Allegro Window", NULL, NULL);

        }

        return 0;
    }

http://alleg.sourceforge.net/a5docs/4.9.14/display.html#allegro_display ALLEGRO_DISPLAY is a struct. — Balu, Jun 04 '14 at 13:05

score 3 · Answer 1 · answered Jun 04 '14 at 13:05

ALLEGRO_DISPLAY "display";

If you want to declare a variable of type ALLEGRO_DISPLAY with the name display, there should not be quotation marks.

But al_create_display returns not a ALLEGRO_DISPLAY, but a pointer to it, so the correct line would be:

ALLEGRO_DISPLAY* display;

Leftium · Answer 2 · 2014-06-04T13:16:55.810

1

Change line 6 to:

ALLEGRO_DISPLAY *display;

This line declares a variable named "display" of type (pointer to) ALLEGRO_DISPLAY. So line 12 should no longer cause an error.

Relevant documentation:

edited Jun 04 '14 at 13:16

answered Jun 04 '14 at 13:05

Leftium

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I am attempting to write a basic first program in allegro

2 Answers2