[fpc-devel] types in xlib unit

Felipe Monteiro de Carvalho felipemonteiro.carvalho at gmail.com
Wed Oct 3 20:41:32 CEST 2007

On 10/3/07, Graeme Geldenhuys <graemeg.lists at gmail.com> wrote:
> In the xlib.pp unit the following types are defined.  How are you
> supposed to work with a record structure that contains nothing?  Does
> it the act like a Pointer type?

It's an opaque structure. You know it's a record, but you don't know
what is inside it =)

An encapsulation techinique common in the c world.

In the end always a pointer to the structure will be used (wither by
really using a pointer or a var parameter), and it is not created or
released on your side of the program, so you don't need to know it's
contents or size or anything else.

Felipe Monteiro de Carvalho

More information about the fpc-devel mailing list