[fpc-pascal]Re: Forward type declaration

[max martinelli]

Hi Hansi... hope this code can help u!! 
(all with in the same "type" block... i.e. do not "interrupt" the "type" block with "const" or "procedure" or "function" or "type")

type
pusb_device  = ^usb_device;
pusb_bus = ^usb_bus;

// .. more typedefs

usb_device  = record
    a: pusb_bus;
    b: pusb_device;
    // x:  usb_device  is invalid (recursive!!!)
    // xx: usb_bus is invalid too. 
    end;

// .. more typedefs

usb_bus = record
    c: pusb_bus;
    d: usb_device ;
    e: pusb_device ;
    // xx: usb_bus is invalid (recursive!!!)    
    end;

warm regards
max

Message: 1
From: Johann Glaser <Johann.Glaser at gmx.at>
To: FPC-Pascal <fpc-pascal at deadlock.et.tudelft.nl>
Organization: 
Date: 23 Apr 2003 21:35:41 +0200
Subject: [fpc-pascal]Forward type declaration
Reply-To: fpc-pascal at lists.freepascal.org

Hi!

Currently I'm translating libusb for FPC. Therefore I used "h2pas".

libusb has two types called usb_device and usb_bus. Both are records.
Each of them has fields, which have ^usb_device and ^usb_bus as types.
So there is a cross type reference between these two records.

In C they simply build a forward type declaration ("struct usb_device;
struct usb_bus;"). In FPC unfortunately this is not possible. Is this
correct? 

Are there any plans to add forward type declarations?

BTW: h2pas crashes with runtime error 216 when it encounters incomplete
type definitions like the above mentioned "struct"s. I'm using the
Debian 1.0.6-1 package of fp-compiler and all other parts.

Bye
  Hansi
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