Re: Why using wrappers for D?

[Mike Wey via Digitalmars-d-learn]

On 10/03/2016 07:19 PM, Chalix wrote:

On Monday, 3 October 2016 at 13:51:28 UTC, Mike Parker wrote:

// wrapfoo.d
import foo;  // import the foo module from above

void myFunc(string s)
{
    import std.string : toStringz;
    my_func(s.toStringz());
}

Thank you for the example, Mike!

And thanks to all others who support me with their answers! I didn't
expect so much answers, the D community seems to be very helpful :)

But there still is one thing, which I don't get:

If I "import foo;" in my project, it will be compiled alongside. So
there is no need for an extra library. Same should be for wrapfoo.d. If
I "import wrapfoo;", I should just need the C-library "foo", and no
D-library "food" right?


To have a more practical example, I looked up the "header" of the GtkD
gtk/Main.d file. There are functions exactly like you described:

public static void init(ref string[] argv)
    {
        int argc = cast(int)argv.length;
        char** outargv = Str.toStringzArray(argv);

        gtk_init(&argc, &outargv);

        argv = Str.toStringArray(outargv, argc);
    }

This function wraps the C-like gtk_init function to a D init function.
The gtk_init function is the function from the GTK+ library, which is
loaded in the gtkc/gtk.d file:

Linker.link(gtk_init, "gtk_init", LIBRARY.GTK);

Linker and link are defined in the gtkc/Loader.d

So, why is it not enough just to "import gtk.Main"? What kind of code is
inside the gtkd-3 library?

The gtkd-3 library contains for example the code you quoted above.

--
Mike Wey